diff --git a/CHANGELOG.md b/CHANGELOG.md
index aa8fafba..020e141f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Changed
 - `setPriority` super json helper can be used to remove priority
 
+### Fixed
+- nullable enum input validation [311](https://github.com/superfaceai/one-sdk-js/issues/311)
+
 ## [2.1.0] - 2022-11-16
 ### Added
 - `multipart/form-data` supports array values to define duplicate fields
diff --git a/src/core/interpreter/profile-parameter-validator.test.ts b/src/core/interpreter/profile-parameter-validator.test.ts
index c28785d3..4775a7c7 100644
--- a/src/core/interpreter/profile-parameter-validator.test.ts
+++ b/src/core/interpreter/profile-parameter-validator.test.ts
@@ -331,6 +331,60 @@ describe('ProfileParameterValidator', () => {
         ).toEqual(true);
       });
 
+      it('should pass with null', () => {
+        expect(
+          parameterValidator.validate({ test: null }, 'input', 'Test').isOk()
+        ).toEqual(true);
+      });
+
+      it('should fail with invalid input', () => {
+        const result1 = parameterValidator.validate(
+          { test: 'none of your business' },
+          'input',
+          'Test'
+        );
+        expect(checkErrorKind(result1)).toEqual(['enumValue']);
+        expect(checkErrorPath(result1)).toEqual([['input', 'test']]);
+        expect(checkErrorContext(result1)).toMatchObject([
+          { actual: '"none of your business"' },
+        ]);
+        const result2 = parameterValidator.validate(
+          { test: 7 },
+          'input',
+          'Test'
+        );
+        expect(checkErrorKind(result2)).toEqual(['enumValue']);
+        expect(checkErrorPath(result2)).toEqual([['input', 'test']]);
+        expect(checkErrorContext(result2)).toMatchObject([{ actual: '7' }]);
+      });
+    });
+
+    describe('AST with non-nullable enum', () => {
+      const ast = parseProfileFromSource(`
+        usecase Test safe {
+          input {
+            test enum { hello, goodbye }!
+          }
+        }
+      `);
+      let parameterValidator: ProfileParameterValidator;
+
+      beforeEach(() => {
+        parameterValidator = new ProfileParameterValidator(ast);
+      });
+
+      it('should pass with valid input', () => {
+        expect(
+          parameterValidator.validate({ test: 'hello' }, 'input', 'Test').isOk()
+        ).toEqual(true);
+      });
+
+      it('should fail with null', () => {
+        expect(
+          parameterValidator.validate({ test: null }, 'input', 'Test').isOk()
+        ).toEqual(false);
+      });
+
       it('should fail with invalid input', () => {
         const result1 = parameterValidator.validate(
           { test: 'none of your business' },
@@ -375,6 +429,12 @@ describe('ProfileParameterValidator', () => {
         ).toEqual(true);
       });
 
+      it('should pass with null', () => {
+        expect(
+          parameterValidator.validate({ test: null }, 'input', 'Test').isOk()
+        ).toEqual(true);
+      });
+
       it('should fail with invalid input', () => {
         const result1 = parameterValidator.validate(
           { test: 'none of your business' },
@@ -410,7 +470,7 @@ describe('ProfileParameterValidator', () => {
         parameterValidator = new ProfileParameterValidator(ast);
       });
 
-      it.each(['A', 'B', 'CC', 'D'])(
+      it.each(['A', 'B', 'CC', 'D', null])(
         'should pass with valid input: %s',
         value => {
           expect(
@@ -934,6 +994,9 @@ describe('ProfileParameterValidator', () => {
         expect(
           parameterValidator.validate({ test: 'c' }, 'result', 'Test').isOk()
         ).toEqual(true);
+        expect(
+          parameterValidator.validate({ test: null }, 'result', 'Test').isOk()
+        ).toEqual(true);
       });
 
       it('should fail with invalid input', () => {
diff --git a/src/core/interpreter/profile-parameter-validator.ts b/src/core/interpreter/profile-parameter-validator.ts
index bc243ee5..a78f8e43 100644
--- a/src/core/interpreter/profile-parameter-validator.ts
+++ b/src/core/interpreter/profile-parameter-validator.ts
@@ -228,7 +228,7 @@ export class ProfileParameterValidator implements ProfileVisitor {
     usecase: string
   ): ValidationFunction {
     return (input: unknown): ValidationResult => {
-      if (input === undefined) {
+      if (input === undefined || input === null) {
         return [true];
       }