diff --git a/.changeset/fluffy-crabs-exercise.md b/.changeset/fluffy-crabs-exercise.md
new file mode 100644
index 000000000..3b54d3ce7
--- /dev/null
+++ b/.changeset/fluffy-crabs-exercise.md
@@ -0,0 +1,5 @@
+---
+"mobx": minor
+---
+
+Replace any with a generic in Set methods
diff --git a/packages/mobx/__tests__/v5/base/typescript-tests.ts b/packages/mobx/__tests__/v5/base/typescript-tests.ts
index 2ce5ef056..c65f66736 100644
--- a/packages/mobx/__tests__/v5/base/typescript-tests.ts
+++ b/packages/mobx/__tests__/v5/base/typescript-tests.ts
@@ -2054,6 +2054,19 @@ test("type inference of the action callback", () => {
     }
 })
 
+test("TS - type inference of Set", () => {
+    const set = observable.set<number>()
+    set.add(1)
+    set.has(1)
+    set.delete(1)
+    // @ts-expect-error
+    set.add("1")
+    // @ts-expect-error
+    set.has("1")
+    // @ts-expect-error
+    set.delete("1")
+})
+
 test("TS - type inference of observe & intercept functions", () => {
     const array = [1, 2]
     const object = { numberKey: 1, stringKey: "string" }
diff --git a/packages/mobx/src/types/observableset.ts b/packages/mobx/src/types/observableset.ts
index 062829acb..05171775a 100644
--- a/packages/mobx/src/types/observableset.ts
+++ b/packages/mobx/src/types/observableset.ts
@@ -159,7 +159,7 @@ export class ObservableSet<T = any> implements Set<T>, IInterceptable<ISetWillCh
         return this
     }
 
-    delete(value: any) {
+    delete(value: T) {
         if (hasInterceptors(this)) {
             const change = interceptChange<ISetWillChange<T>>(this, {
                 type: DELETE,
@@ -202,7 +202,7 @@ export class ObservableSet<T = any> implements Set<T>, IInterceptable<ISetWillCh
         return false
     }
 
-    has(value: any) {
+    has(value: T) {
         this.atom_.reportObserved()
         return this.data_.has(this.dehanceValue_(value))
     }