diff --git a/src/myzod/index.ts b/src/myzod/index.ts
index ce3bdae2..6b47c454 100644
--- a/src/myzod/index.ts
+++ b/src/myzod/index.ts
@@ -212,9 +212,8 @@ const generateFieldTypeMyZodSchema = (
     }
     const appliedDirectivesGen = applyDirectives(config, field, gen);
     if (isNonNullType(parentType)) {
-      if (config.notAllowEmptyString === true) {
-        const tsType = visitor.getScalarType(type.name.value);
-        if (tsType === 'string') return `${gen}.min(1)`;
+      if (visitor.shouldEmitAsNotAllowEmptyString(type.name.value)) {
+        return `${gen}.min(1)`;
       }
       return appliedDirectivesGen;
     }
diff --git a/src/visitor.ts b/src/visitor.ts
index 574cce3c..d95b1892 100644
--- a/src/visitor.ts
+++ b/src/visitor.ts
@@ -1,5 +1,5 @@
 import { TsVisitor } from '@graphql-codegen/typescript';
-import { GraphQLSchema, NameNode } from 'graphql';
+import { GraphQLSchema, NameNode, specifiedScalarTypes } from 'graphql';
 
 import { ValidationSchemaPluginConfig } from './config';
 
@@ -7,9 +7,13 @@ export class Visitor extends TsVisitor {
   constructor(
     private scalarDirection: 'input' | 'output' | 'both',
     private schema: GraphQLSchema,
-    config: ValidationSchemaPluginConfig
+    private pluginConfig: ValidationSchemaPluginConfig
   ) {
-    super(schema, config);
+    super(schema, pluginConfig);
+  }
+
+  private isSpecifiedScalarName(scalarName: string) {
+    return specifiedScalarTypes.some(({ name }) => name === scalarName);
   }
 
   public getType(name: string) {
@@ -34,4 +38,16 @@ export class Visitor extends TsVisitor {
     }
     return this.scalars[scalarName][this.scalarDirection];
   }
+
+  public shouldEmitAsNotAllowEmptyString(name: string): boolean {
+    if (this.pluginConfig.notAllowEmptyString !== true) {
+      return false;
+    }
+    const typ = this.getType(name);
+    if (typ?.astNode?.kind !== 'ScalarTypeDefinition' && !this.isSpecifiedScalarName(name)) {
+      return false;
+    }
+    const tsType = this.getScalarType(name);
+    return tsType === 'string';
+  }
 }
diff --git a/src/yup/index.ts b/src/yup/index.ts
index a9a335fe..4aeb38b8 100644
--- a/src/yup/index.ts
+++ b/src/yup/index.ts
@@ -262,9 +262,8 @@ const generateFieldTypeYupSchema = (
   if (isNamedType(type)) {
     const gen = generateNameNodeYupSchema(config, visitor, type.name);
     if (isNonNullType(parentType)) {
-      if (config.notAllowEmptyString === true) {
-        const tsType = visitor.getScalarType(type.name.value);
-        if (tsType === 'string') return `${gen}.required()`;
+      if (visitor.shouldEmitAsNotAllowEmptyString(type.name.value)) {
+        return `${gen}.required()`;
       }
       return `${gen}.nonNullable()`;
     }
diff --git a/src/zod/index.ts b/src/zod/index.ts
index 96321313..3d01931c 100644
--- a/src/zod/index.ts
+++ b/src/zod/index.ts
@@ -222,9 +222,8 @@ const generateFieldTypeZodSchema = (
     }
     const appliedDirectivesGen = applyDirectives(config, field, gen);
     if (isNonNullType(parentType)) {
-      if (config.notAllowEmptyString === true) {
-        const tsType = visitor.getScalarType(type.name.value);
-        if (tsType === 'string') return `${appliedDirectivesGen}.min(1)`;
+      if (visitor.shouldEmitAsNotAllowEmptyString(type.name.value)) {
+        return `${appliedDirectivesGen}.min(1)`;
       }
       return appliedDirectivesGen;
     }
diff --git a/tests/myzod.spec.ts b/tests/myzod.spec.ts
index 62170d00..0bbf7e8a 100644
--- a/tests/myzod.spec.ts
+++ b/tests/myzod.spec.ts
@@ -1,4 +1,5 @@
 import { buildSchema } from 'graphql';
+import dedent from 'ts-dedent';
 
 import { plugin } from '../src/index';
 
@@ -297,6 +298,37 @@ describe('myzod', () => {
     }
   });
 
+  it('with notAllowEmptyString issue #386', async () => {
+    const schema = buildSchema(/* GraphQL */ `
+      input InputOne {
+        field: InputNested!
+      }
+
+      input InputNested {
+        field: String!
+      }
+    `);
+    const result = await plugin(
+      schema,
+      [],
+      {
+        schema: 'myzod',
+        notAllowEmptyString: true,
+        scalars: {
+          ID: 'string',
+        },
+      },
+      {}
+    );
+    const wantContain = dedent`
+    export function InputNestedSchema(): myzod.Type<InputNested> {
+      return myzod.object({
+        field: myzod.string().min(1)
+      })
+    }`;
+    expect(result.content).toContain(wantContain);
+  });
+
   it('with scalarSchemas', async () => {
     const schema = buildSchema(/* GraphQL */ `
       input ScalarsInput {
diff --git a/tests/yup.spec.ts b/tests/yup.spec.ts
index 419b10d4..86fd10d7 100644
--- a/tests/yup.spec.ts
+++ b/tests/yup.spec.ts
@@ -1,4 +1,5 @@
 import { buildSchema } from 'graphql';
+import dedent from 'ts-dedent';
 
 import { plugin } from '../src/index';
 
@@ -294,6 +295,37 @@ describe('yup', () => {
     }
   });
 
+  it('with notAllowEmptyString issue #386', async () => {
+    const schema = buildSchema(/* GraphQL */ `
+      input InputOne {
+        field: InputNested!
+      }
+
+      input InputNested {
+        field: String!
+      }
+    `);
+    const result = await plugin(
+      schema,
+      [],
+      {
+        schema: 'yup',
+        notAllowEmptyString: true,
+        scalars: {
+          ID: 'string',
+        },
+      },
+      {}
+    );
+    const wantContain = dedent`
+    export function InputNestedSchema(): yup.ObjectSchema<InputNested> {
+      return yup.object({
+        field: yup.string().defined().required()
+      })
+    }`;
+    expect(result.content).toContain(wantContain);
+  });
+
   it('with scalarSchemas', async () => {
     const schema = buildSchema(/* GraphQL */ `
       input ScalarsInput {
diff --git a/tests/zod.spec.ts b/tests/zod.spec.ts
index 74615604..68f223da 100644
--- a/tests/zod.spec.ts
+++ b/tests/zod.spec.ts
@@ -1,4 +1,5 @@
 import { buildSchema } from 'graphql';
+import { dedent } from 'ts-dedent';
 
 import { plugin } from '../src/index';
 
@@ -297,6 +298,37 @@ describe('zod', () => {
     }
   });
 
+  it('with notAllowEmptyString issue #386', async () => {
+    const schema = buildSchema(/* GraphQL */ `
+      input InputOne {
+        field: InputNested!
+      }
+
+      input InputNested {
+        field: String!
+      }
+    `);
+    const result = await plugin(
+      schema,
+      [],
+      {
+        schema: 'zod',
+        notAllowEmptyString: true,
+        scalars: {
+          ID: 'string',
+        },
+      },
+      {}
+    );
+    const wantContain = dedent`
+    export function InputNestedSchema(): z.ZodObject<Properties<InputNested>> {
+      return z.object({
+        field: z.string().min(1)
+      })
+    }`;
+    expect(result.content).toContain(wantContain);
+  });
+
   it('with scalarSchemas', async () => {
     const schema = buildSchema(/* GraphQL */ `
       input ScalarsInput {