diff --git a/src/lib/es5.d.ts b/src/lib/es5.d.ts
index a74b3cb4c2111..4609db2e92aaf 100644
--- a/src/lib/es5.d.ts
+++ b/src/lib/es5.d.ts
@@ -1582,7 +1582,9 @@ type Extract<T, U> = T extends U ? T : never;
 /**
  * Construct a type with the properties of T except for those in type K.
  */
-type Omit<T, K extends keyof any> = Pick<T, Exclude<keyof T, K>>;
+type Omit<T, K extends keyof any> = {
+    [P in keyof T as Exclude<P, K>]: T[P];
+};
 
 /**
  * Exclude null and undefined from T
diff --git a/tests/baselines/reference/destructuringUnspreadableIntoRest.symbols b/tests/baselines/reference/destructuringUnspreadableIntoRest.symbols
index 557afeeffa912..5a05c37175e96 100644
--- a/tests/baselines/reference/destructuringUnspreadableIntoRest.symbols
+++ b/tests/baselines/reference/destructuringUnspreadableIntoRest.symbols
@@ -50,9 +50,9 @@ class A {
 >A : Symbol(A, Decl(destructuringUnspreadableIntoRest.ts, 0, 0))
 
         rest1.publicProp;
->rest1.publicProp : Symbol(publicProp, Decl(destructuringUnspreadableIntoRest.ts, 1, 16))
+>rest1.publicProp : Symbol(publicProp)
 >rest1 : Symbol(rest1, Decl(destructuringUnspreadableIntoRest.ts, 14, 15))
->publicProp : Symbol(publicProp, Decl(destructuringUnspreadableIntoRest.ts, 1, 16))
+>publicProp : Symbol(publicProp)
 
         rest2.publicProp;
 >rest2.publicProp : Symbol(A.publicProp, Decl(destructuringUnspreadableIntoRest.ts, 1, 16))
@@ -157,9 +157,9 @@ function destructure<T extends A>(x: T) {
 >A : Symbol(A, Decl(destructuringUnspreadableIntoRest.ts, 0, 0))
 
     rest1.publicProp;
->rest1.publicProp : Symbol(publicProp, Decl(destructuringUnspreadableIntoRest.ts, 1, 16))
+>rest1.publicProp : Symbol(publicProp)
 >rest1 : Symbol(rest1, Decl(destructuringUnspreadableIntoRest.ts, 52, 11))
->publicProp : Symbol(publicProp, Decl(destructuringUnspreadableIntoRest.ts, 1, 16))
+>publicProp : Symbol(publicProp)
 
     rest2.publicProp;
 >rest2.publicProp : Symbol(A.publicProp, Decl(destructuringUnspreadableIntoRest.ts, 1, 16))
diff --git a/tests/baselines/reference/genericObjectSpreadResultInSwitch.symbols b/tests/baselines/reference/genericObjectSpreadResultInSwitch.symbols
index 56868aee4e94f..aa6f806f7582d 100644
--- a/tests/baselines/reference/genericObjectSpreadResultInSwitch.symbols
+++ b/tests/baselines/reference/genericObjectSpreadResultInSwitch.symbols
@@ -48,10 +48,10 @@ switch (params.tag) {
         // TS 4.3: string | number
         const result = getType(params).type;
 >result : Symbol(result, Decl(genericObjectSpreadResultInSwitch.ts, 21, 13))
->getType(params).type : Symbol(type, Decl(genericObjectSpreadResultInSwitch.ts, 2, 16))
+>getType(params).type : Symbol(type)
 >getType : Symbol(getType, Decl(genericObjectSpreadResultInSwitch.ts, 4, 5))
 >params : Symbol(params, Decl(genericObjectSpreadResultInSwitch.ts, 15, 13))
->type : Symbol(type, Decl(genericObjectSpreadResultInSwitch.ts, 2, 16))
+>type : Symbol(type)
 
         break;
     }
@@ -60,10 +60,10 @@ switch (params.tag) {
         // TS 4.3: string | number
         const result = getType(params).type;
 >result : Symbol(result, Decl(genericObjectSpreadResultInSwitch.ts, 28, 13))
->getType(params).type : Symbol(type, Decl(genericObjectSpreadResultInSwitch.ts, 2, 45))
+>getType(params).type : Symbol(type)
 >getType : Symbol(getType, Decl(genericObjectSpreadResultInSwitch.ts, 4, 5))
 >params : Symbol(params, Decl(genericObjectSpreadResultInSwitch.ts, 15, 13))
->type : Symbol(type, Decl(genericObjectSpreadResultInSwitch.ts, 2, 45))
+>type : Symbol(type)
 
         break;
     }
diff --git a/tests/baselines/reference/keyofGenericExtendingClassDoubleLayer.types b/tests/baselines/reference/keyofGenericExtendingClassDoubleLayer.types
index d3108ac94a927..bf7cf6f1f88a8 100644
--- a/tests/baselines/reference/keyofGenericExtendingClassDoubleLayer.types
+++ b/tests/baselines/reference/keyofGenericExtendingClassDoubleLayer.types
@@ -7,11 +7,11 @@ class Model<Attributes = any> {
 }
 
 type ModelAttributes<T> = Omit<T, keyof Model>;
->ModelAttributes : ModelAttributes<T>
+>ModelAttributes : Omit<T, "createdAt">
 
 class AutoModel<T> extends Model<ModelAttributes<T>> {}
 >AutoModel : AutoModel<T>
->Model : Model<ModelAttributes<T>>
+>Model : Model<Omit<T, "createdAt">>
 
 class PersonModel extends AutoModel<PersonModel> {
 >PersonModel : PersonModel
diff --git a/tests/baselines/reference/mappedTypeConstraints.symbols b/tests/baselines/reference/mappedTypeConstraints.symbols
index 3601ffc3de848..4a793fd0dc388 100644
--- a/tests/baselines/reference/mappedTypeConstraints.symbols
+++ b/tests/baselines/reference/mappedTypeConstraints.symbols
@@ -132,9 +132,9 @@ const modifier = <T extends TargetProps>(targetProps: T) => {
 >targetProps : Symbol(targetProps, Decl(mappedTypeConstraints.ts, 30, 41))
 
     rest.foo;
->rest.foo : Symbol(foo, Decl(mappedTypeConstraints.ts, 25, 20))
+>rest.foo : Symbol(foo)
 >rest : Symbol(rest, Decl(mappedTypeConstraints.ts, 31, 13))
->foo : Symbol(foo, Decl(mappedTypeConstraints.ts, 25, 20))
+>foo : Symbol(foo)
 
 };
 
diff --git a/tests/baselines/reference/omitOfTypeExtendingIndexSignature.js b/tests/baselines/reference/omitOfTypeExtendingIndexSignature.js
new file mode 100644
index 0000000000000..8b7542745d819
--- /dev/null
+++ b/tests/baselines/reference/omitOfTypeExtendingIndexSignature.js
@@ -0,0 +1,13 @@
+//// [omitOfTypeExtendingIndexSignature.ts]
+// #36981
+type AnyRecord = Record<string, any>;
+interface ExtendsAny extends AnyRecord {
+    myKey1: string;
+    myKey2: string;
+}
+
+type OmitsKey = Omit<ExtendsAny, "myKey2">;
+type OmitsKey1 = OmitsKey["myKey1"]; // should be `string`
+type OmitsKey2 = OmitsKey["myKey2"]; // should be `any`
+
+//// [omitOfTypeExtendingIndexSignature.js]
diff --git a/tests/baselines/reference/omitOfTypeExtendingIndexSignature.symbols b/tests/baselines/reference/omitOfTypeExtendingIndexSignature.symbols
new file mode 100644
index 0000000000000..108de9094a691
--- /dev/null
+++ b/tests/baselines/reference/omitOfTypeExtendingIndexSignature.symbols
@@ -0,0 +1,30 @@
+=== tests/cases/compiler/omitOfTypeExtendingIndexSignature.ts ===
+// #36981
+type AnyRecord = Record<string, any>;
+>AnyRecord : Symbol(AnyRecord, Decl(omitOfTypeExtendingIndexSignature.ts, 0, 0))
+>Record : Symbol(Record, Decl(lib.es5.d.ts, --, --))
+
+interface ExtendsAny extends AnyRecord {
+>ExtendsAny : Symbol(ExtendsAny, Decl(omitOfTypeExtendingIndexSignature.ts, 1, 37))
+>AnyRecord : Symbol(AnyRecord, Decl(omitOfTypeExtendingIndexSignature.ts, 0, 0))
+
+    myKey1: string;
+>myKey1 : Symbol(ExtendsAny.myKey1, Decl(omitOfTypeExtendingIndexSignature.ts, 2, 40))
+
+    myKey2: string;
+>myKey2 : Symbol(ExtendsAny.myKey2, Decl(omitOfTypeExtendingIndexSignature.ts, 3, 19))
+}
+
+type OmitsKey = Omit<ExtendsAny, "myKey2">;
+>OmitsKey : Symbol(OmitsKey, Decl(omitOfTypeExtendingIndexSignature.ts, 5, 1))
+>Omit : Symbol(Omit, Decl(lib.es5.d.ts, --, --))
+>ExtendsAny : Symbol(ExtendsAny, Decl(omitOfTypeExtendingIndexSignature.ts, 1, 37))
+
+type OmitsKey1 = OmitsKey["myKey1"]; // should be `string`
+>OmitsKey1 : Symbol(OmitsKey1, Decl(omitOfTypeExtendingIndexSignature.ts, 7, 43))
+>OmitsKey : Symbol(OmitsKey, Decl(omitOfTypeExtendingIndexSignature.ts, 5, 1))
+
+type OmitsKey2 = OmitsKey["myKey2"]; // should be `any`
+>OmitsKey2 : Symbol(OmitsKey2, Decl(omitOfTypeExtendingIndexSignature.ts, 8, 36))
+>OmitsKey : Symbol(OmitsKey, Decl(omitOfTypeExtendingIndexSignature.ts, 5, 1))
+
diff --git a/tests/baselines/reference/omitOfTypeExtendingIndexSignature.types b/tests/baselines/reference/omitOfTypeExtendingIndexSignature.types
new file mode 100644
index 0000000000000..6a7f30dae849e
--- /dev/null
+++ b/tests/baselines/reference/omitOfTypeExtendingIndexSignature.types
@@ -0,0 +1,22 @@
+=== tests/cases/compiler/omitOfTypeExtendingIndexSignature.ts ===
+// #36981
+type AnyRecord = Record<string, any>;
+>AnyRecord : { [x: string]: any; }
+
+interface ExtendsAny extends AnyRecord {
+    myKey1: string;
+>myKey1 : string
+
+    myKey2: string;
+>myKey2 : string
+}
+
+type OmitsKey = Omit<ExtendsAny, "myKey2">;
+>OmitsKey : Omit<ExtendsAny, "myKey2">
+
+type OmitsKey1 = OmitsKey["myKey1"]; // should be `string`
+>OmitsKey1 : string
+
+type OmitsKey2 = OmitsKey["myKey2"]; // should be `any`
+>OmitsKey2 : any
+
diff --git a/tests/baselines/reference/omitTypeHelperModifiers01.symbols b/tests/baselines/reference/omitTypeHelperModifiers01.symbols
index 39a3360678138..a5cc8be34f303 100644
--- a/tests/baselines/reference/omitTypeHelperModifiers01.symbols
+++ b/tests/baselines/reference/omitTypeHelperModifiers01.symbols
@@ -28,42 +28,42 @@ function f(x: B) {
 
     const b = x.b;
 >b : Symbol(b, Decl(omitTypeHelperModifiers01.ts, 10, 9))
->x.b : Symbol(b, Decl(omitTypeHelperModifiers01.ts, 1, 14))
+>x.b : Symbol(b)
 >x : Symbol(x, Decl(omitTypeHelperModifiers01.ts, 9, 11))
->b : Symbol(b, Decl(omitTypeHelperModifiers01.ts, 1, 14))
+>b : Symbol(b)
 
     x.b = "hello";
->x.b : Symbol(b, Decl(omitTypeHelperModifiers01.ts, 1, 14))
+>x.b : Symbol(b)
 >x : Symbol(x, Decl(omitTypeHelperModifiers01.ts, 9, 11))
->b : Symbol(b, Decl(omitTypeHelperModifiers01.ts, 1, 14))
+>b : Symbol(b)
 
     x.b = undefined;
->x.b : Symbol(b, Decl(omitTypeHelperModifiers01.ts, 1, 14))
+>x.b : Symbol(b)
 >x : Symbol(x, Decl(omitTypeHelperModifiers01.ts, 9, 11))
->b : Symbol(b, Decl(omitTypeHelperModifiers01.ts, 1, 14))
+>b : Symbol(b)
 >undefined : Symbol(undefined)
 
     const c = x.c;
 >c : Symbol(c, Decl(omitTypeHelperModifiers01.ts, 14, 9))
->x.c : Symbol(c, Decl(omitTypeHelperModifiers01.ts, 2, 15))
+>x.c : Symbol(c)
 >x : Symbol(x, Decl(omitTypeHelperModifiers01.ts, 9, 11))
->c : Symbol(c, Decl(omitTypeHelperModifiers01.ts, 2, 15))
+>c : Symbol(c)
 
     x.c = true;
->x.c : Symbol(c, Decl(omitTypeHelperModifiers01.ts, 2, 15))
+>x.c : Symbol(c)
 >x : Symbol(x, Decl(omitTypeHelperModifiers01.ts, 9, 11))
->c : Symbol(c, Decl(omitTypeHelperModifiers01.ts, 2, 15))
+>c : Symbol(c)
 
     const d = x.d;
 >d : Symbol(d, Decl(omitTypeHelperModifiers01.ts, 17, 9))
->x.d : Symbol(d, Decl(omitTypeHelperModifiers01.ts, 3, 24))
+>x.d : Symbol(d)
 >x : Symbol(x, Decl(omitTypeHelperModifiers01.ts, 9, 11))
->d : Symbol(d, Decl(omitTypeHelperModifiers01.ts, 3, 24))
+>d : Symbol(d)
 
     x.d = d;
->x.d : Symbol(d, Decl(omitTypeHelperModifiers01.ts, 3, 24))
+>x.d : Symbol(d)
 >x : Symbol(x, Decl(omitTypeHelperModifiers01.ts, 9, 11))
->d : Symbol(d, Decl(omitTypeHelperModifiers01.ts, 3, 24))
+>d : Symbol(d)
 >d : Symbol(d, Decl(omitTypeHelperModifiers01.ts, 17, 9))
 }
 
diff --git a/tests/baselines/reference/omitTypeHelperModifiers01.types b/tests/baselines/reference/omitTypeHelperModifiers01.types
index e956f06352f64..a3054e9bfe87c 100644
--- a/tests/baselines/reference/omitTypeHelperModifiers01.types
+++ b/tests/baselines/reference/omitTypeHelperModifiers01.types
@@ -17,55 +17,55 @@ type A = {
 };
 
 type B = Omit<A, 'a'>;
->B : { b?: string | undefined; readonly c: boolean; d: unknown; }
+>B : Omit<A, "a">
 
 function f(x: B) {
 >f : (x: B) => void
->x : B
+>x : Omit<A, "a">
 
     const b = x.b;
 >b : string | undefined
 >x.b : string | undefined
->x : B
+>x : Omit<A, "a">
 >b : string | undefined
 
     x.b = "hello";
 >x.b = "hello" : "hello"
 >x.b : string | undefined
->x : B
+>x : Omit<A, "a">
 >b : string | undefined
 >"hello" : "hello"
 
     x.b = undefined;
 >x.b = undefined : undefined
 >x.b : string | undefined
->x : B
+>x : Omit<A, "a">
 >b : string | undefined
 >undefined : undefined
 
     const c = x.c;
 >c : boolean
 >x.c : boolean
->x : B
+>x : Omit<A, "a">
 >c : boolean
 
     x.c = true;
 >x.c = true : true
 >x.c : any
->x : B
+>x : Omit<A, "a">
 >c : any
 >true : true
 
     const d = x.d;
 >d : unknown
 >x.d : unknown
->x : B
+>x : Omit<A, "a">
 >d : unknown
 
     x.d = d;
 >x.d = d : unknown
 >x.d : unknown
->x : B
+>x : Omit<A, "a">
 >d : unknown
 >d : unknown
 }
diff --git a/tests/baselines/reference/omitTypeTestErrors01.errors.txt b/tests/baselines/reference/omitTypeTestErrors01.errors.txt
index 9a363e767951d..6b65e292b55f4 100644
--- a/tests/baselines/reference/omitTypeTestErrors01.errors.txt
+++ b/tests/baselines/reference/omitTypeTestErrors01.errors.txt
@@ -1,5 +1,5 @@
-tests/cases/compiler/omitTypeTestErrors01.ts(11,16): error TS2339: Property 'c' does not exist on type 'Bar'.
-tests/cases/compiler/omitTypeTestErrors01.ts(15,16): error TS2339: Property 'b' does not exist on type 'Baz'.
+tests/cases/compiler/omitTypeTestErrors01.ts(11,16): error TS2339: Property 'c' does not exist on type 'Omit<Foo, "c">'.
+tests/cases/compiler/omitTypeTestErrors01.ts(15,16): error TS2339: Property 'b' does not exist on type 'Omit<Foo, "c" | "b">'.
 
 
 ==== tests/cases/compiler/omitTypeTestErrors01.ts (2 errors) ====
@@ -15,13 +15,13 @@ tests/cases/compiler/omitTypeTestErrors01.ts(15,16): error TS2339: Property 'b'
     export function getBarC(bar: Bar) {
         return bar.c;
                    ~
-!!! error TS2339: Property 'c' does not exist on type 'Bar'.
+!!! error TS2339: Property 'c' does not exist on type 'Omit<Foo, "c">'.
     }
     
     export function getBazB(baz: Baz) {
         return baz.b;
                    ~
-!!! error TS2339: Property 'b' does not exist on type 'Baz'.
+!!! error TS2339: Property 'b' does not exist on type 'Omit<Foo, "c" | "b">'.
     }
     
     
\ No newline at end of file
diff --git a/tests/baselines/reference/omitTypeTestErrors01.types b/tests/baselines/reference/omitTypeTestErrors01.types
index f341e33cc0640..5a5935126682e 100644
--- a/tests/baselines/reference/omitTypeTestErrors01.types
+++ b/tests/baselines/reference/omitTypeTestErrors01.types
@@ -11,28 +11,28 @@ interface Foo {
 }
 
 export type Bar = Omit<Foo, "c">;
->Bar : { a: string; b: number; }
+>Bar : Omit<Foo, "c">
 
 export type Baz = Omit<Foo, "b" | "c">;
->Baz : { a: string; }
+>Baz : Omit<Foo, "c" | "b">
 
 export function getBarC(bar: Bar) {
 >getBarC : (bar: Bar) => any
->bar : Bar
+>bar : Omit<Foo, "c">
 
     return bar.c;
 >bar.c : any
->bar : Bar
+>bar : Omit<Foo, "c">
 >c : any
 }
 
 export function getBazB(baz: Baz) {
 >getBazB : (baz: Baz) => any
->baz : Baz
+>baz : Omit<Foo, "c" | "b">
 
     return baz.b;
 >baz.b : any
->baz : Baz
+>baz : Omit<Foo, "c" | "b">
 >b : any
 }
 
diff --git a/tests/baselines/reference/omitTypeTests01.symbols b/tests/baselines/reference/omitTypeTests01.symbols
index d614f65daff03..93b492917855a 100644
--- a/tests/baselines/reference/omitTypeTests01.symbols
+++ b/tests/baselines/reference/omitTypeTests01.symbols
@@ -28,9 +28,9 @@ export function getBarA(bar: Bar) {
 >Bar : Symbol(Bar, Decl(omitTypeTests01.ts, 4, 1))
 
     return bar.a;
->bar.a : Symbol(a, Decl(omitTypeTests01.ts, 0, 15))
+>bar.a : Symbol(a)
 >bar : Symbol(bar, Decl(omitTypeTests01.ts, 9, 24))
->a : Symbol(a, Decl(omitTypeTests01.ts, 0, 15))
+>a : Symbol(a)
 }
 
 export function getBazA(baz: Baz) {
@@ -39,9 +39,9 @@ export function getBazA(baz: Baz) {
 >Baz : Symbol(Baz, Decl(omitTypeTests01.ts, 6, 33))
 
     return baz.a;
->baz.a : Symbol(a, Decl(omitTypeTests01.ts, 0, 15))
+>baz.a : Symbol(a)
 >baz : Symbol(baz, Decl(omitTypeTests01.ts, 13, 24))
->a : Symbol(a, Decl(omitTypeTests01.ts, 0, 15))
+>a : Symbol(a)
 }
 
 
diff --git a/tests/baselines/reference/omitTypeTests01.types b/tests/baselines/reference/omitTypeTests01.types
index 6a270844af5b5..f0f5b0627a69a 100644
--- a/tests/baselines/reference/omitTypeTests01.types
+++ b/tests/baselines/reference/omitTypeTests01.types
@@ -11,28 +11,28 @@ interface Foo {
 }
 
 export type Bar = Omit<Foo, "c">;
->Bar : { a: string; b: number; }
+>Bar : Omit<Foo, "c">
 
 export type Baz = Omit<Foo, "b" | "c">;
->Baz : { a: string; }
+>Baz : Omit<Foo, "c" | "b">
 
 export function getBarA(bar: Bar) {
 >getBarA : (bar: Bar) => string
->bar : Bar
+>bar : Omit<Foo, "c">
 
     return bar.a;
 >bar.a : string
->bar : Bar
+>bar : Omit<Foo, "c">
 >a : string
 }
 
 export function getBazA(baz: Baz) {
 >getBazA : (baz: Baz) => string
->baz : Baz
+>baz : Omit<Foo, "c" | "b">
 
     return baz.a;
 >baz.a : string
->baz : Baz
+>baz : Omit<Foo, "c" | "b">
 >a : string
 }
 
diff --git a/tests/baselines/reference/staticIndexSignature5.types b/tests/baselines/reference/staticIndexSignature5.types
index 2f3ea91f8cfc2..4be91c8241ba1 100644
--- a/tests/baselines/reference/staticIndexSignature5.types
+++ b/tests/baselines/reference/staticIndexSignature5.types
@@ -45,9 +45,9 @@ type TFI = Pick<I, number>
 >TFI : { [x: number]: 42 | 233; }
 
 type TG = Omit<typeof B, number>
->TG : { [x: string]: number; }
+>TG : Omit<typeof B, number>
 >B : typeof B
 
 type TGI = Omit<I, number>
->TGI : { [x: string]: number; }
+>TGI : Omit<I, number>
 
diff --git a/tests/cases/compiler/omitOfTypeExtendingIndexSignature.ts b/tests/cases/compiler/omitOfTypeExtendingIndexSignature.ts
new file mode 100644
index 0000000000000..721492b992580
--- /dev/null
+++ b/tests/cases/compiler/omitOfTypeExtendingIndexSignature.ts
@@ -0,0 +1,10 @@
+// #36981
+type AnyRecord = Record<string, any>;
+interface ExtendsAny extends AnyRecord {
+    myKey1: string;
+    myKey2: string;
+}
+
+type OmitsKey = Omit<ExtendsAny, "myKey2">;
+type OmitsKey1 = OmitsKey["myKey1"]; // should be `string`
+type OmitsKey2 = OmitsKey["myKey2"]; // should be `any`
\ No newline at end of file