diff --git a/modules/openapi-generator/src/main/resources/typescript-fetch/runtime.mustache b/modules/openapi-generator/src/main/resources/typescript-fetch/runtime.mustache
index bd53174f179c..8fb973acae64 100644
--- a/modules/openapi-generator/src/main/resources/typescript-fetch/runtime.mustache
+++ b/modules/openapi-generator/src/main/resources/typescript-fetch/runtime.mustache
@@ -49,7 +49,7 @@ export class BaseAPI {
             // do not handle correctly sometimes.
             url += '?' + this.configuration.queryParamsStringify(context.query);
         }
-        const body = (context.body instanceof FormData || isBlob(context.body))
+        const body = (context.body instanceof FormData || context.body instanceof URLSearchParams || isBlob(context.body))
 	    ? context.body
 	    : JSON.stringify(context.body);
 
diff --git a/samples/client/petstore/typescript-fetch/builds/default/src/runtime.ts b/samples/client/petstore/typescript-fetch/builds/default/src/runtime.ts
index 473d2e72316c..8aa68ea78f3a 100644
--- a/samples/client/petstore/typescript-fetch/builds/default/src/runtime.ts
+++ b/samples/client/petstore/typescript-fetch/builds/default/src/runtime.ts
@@ -60,7 +60,7 @@ export class BaseAPI {
             // do not handle correctly sometimes.
             url += '?' + this.configuration.queryParamsStringify(context.query);
         }
-        const body = (context.body instanceof FormData || isBlob(context.body))
+        const body = (context.body instanceof FormData || context.body instanceof URLSearchParams || isBlob(context.body))
 	    ? context.body
 	    : JSON.stringify(context.body);
 
diff --git a/samples/client/petstore/typescript-fetch/builds/es6-target/src/runtime.ts b/samples/client/petstore/typescript-fetch/builds/es6-target/src/runtime.ts
index 473d2e72316c..8aa68ea78f3a 100644
--- a/samples/client/petstore/typescript-fetch/builds/es6-target/src/runtime.ts
+++ b/samples/client/petstore/typescript-fetch/builds/es6-target/src/runtime.ts
@@ -60,7 +60,7 @@ export class BaseAPI {
             // do not handle correctly sometimes.
             url += '?' + this.configuration.queryParamsStringify(context.query);
         }
-        const body = (context.body instanceof FormData || isBlob(context.body))
+        const body = (context.body instanceof FormData || context.body instanceof URLSearchParams || isBlob(context.body))
 	    ? context.body
 	    : JSON.stringify(context.body);
 
diff --git a/samples/client/petstore/typescript-fetch/builds/multiple-parameters/src/runtime.ts b/samples/client/petstore/typescript-fetch/builds/multiple-parameters/src/runtime.ts
index 473d2e72316c..8aa68ea78f3a 100644
--- a/samples/client/petstore/typescript-fetch/builds/multiple-parameters/src/runtime.ts
+++ b/samples/client/petstore/typescript-fetch/builds/multiple-parameters/src/runtime.ts
@@ -60,7 +60,7 @@ export class BaseAPI {
             // do not handle correctly sometimes.
             url += '?' + this.configuration.queryParamsStringify(context.query);
         }
-        const body = (context.body instanceof FormData || isBlob(context.body))
+        const body = (context.body instanceof FormData || context.body instanceof URLSearchParams || isBlob(context.body))
 	    ? context.body
 	    : JSON.stringify(context.body);
 
diff --git a/samples/client/petstore/typescript-fetch/builds/prefix-parameter-interfaces/src/runtime.ts b/samples/client/petstore/typescript-fetch/builds/prefix-parameter-interfaces/src/runtime.ts
index 473d2e72316c..8aa68ea78f3a 100644
--- a/samples/client/petstore/typescript-fetch/builds/prefix-parameter-interfaces/src/runtime.ts
+++ b/samples/client/petstore/typescript-fetch/builds/prefix-parameter-interfaces/src/runtime.ts
@@ -60,7 +60,7 @@ export class BaseAPI {
             // do not handle correctly sometimes.
             url += '?' + this.configuration.queryParamsStringify(context.query);
         }
-        const body = (context.body instanceof FormData || isBlob(context.body))
+        const body = (context.body instanceof FormData || context.body instanceof URLSearchParams || isBlob(context.body))
 	    ? context.body
 	    : JSON.stringify(context.body);
 
diff --git a/samples/client/petstore/typescript-fetch/builds/typescript-three-plus/src/runtime.ts b/samples/client/petstore/typescript-fetch/builds/typescript-three-plus/src/runtime.ts
index aa2ef6158928..8fdddb5a69e4 100644
--- a/samples/client/petstore/typescript-fetch/builds/typescript-three-plus/src/runtime.ts
+++ b/samples/client/petstore/typescript-fetch/builds/typescript-three-plus/src/runtime.ts
@@ -60,7 +60,7 @@ export class BaseAPI {
             // do not handle correctly sometimes.
             url += '?' + this.configuration.queryParamsStringify(context.query);
         }
-        const body = (context.body instanceof FormData || isBlob(context.body))
+        const body = (context.body instanceof FormData || context.body instanceof URLSearchParams || isBlob(context.body))
 	    ? context.body
 	    : JSON.stringify(context.body);
 
diff --git a/samples/client/petstore/typescript-fetch/builds/with-interfaces/src/runtime.ts b/samples/client/petstore/typescript-fetch/builds/with-interfaces/src/runtime.ts
index 473d2e72316c..8aa68ea78f3a 100644
--- a/samples/client/petstore/typescript-fetch/builds/with-interfaces/src/runtime.ts
+++ b/samples/client/petstore/typescript-fetch/builds/with-interfaces/src/runtime.ts
@@ -60,7 +60,7 @@ export class BaseAPI {
             // do not handle correctly sometimes.
             url += '?' + this.configuration.queryParamsStringify(context.query);
         }
-        const body = (context.body instanceof FormData || isBlob(context.body))
+        const body = (context.body instanceof FormData || context.body instanceof URLSearchParams || isBlob(context.body))
 	    ? context.body
 	    : JSON.stringify(context.body);
 
diff --git a/samples/client/petstore/typescript-fetch/builds/with-npm-version/src/runtime.ts b/samples/client/petstore/typescript-fetch/builds/with-npm-version/src/runtime.ts
index 473d2e72316c..8aa68ea78f3a 100644
--- a/samples/client/petstore/typescript-fetch/builds/with-npm-version/src/runtime.ts
+++ b/samples/client/petstore/typescript-fetch/builds/with-npm-version/src/runtime.ts
@@ -60,7 +60,7 @@ export class BaseAPI {
             // do not handle correctly sometimes.
             url += '?' + this.configuration.queryParamsStringify(context.query);
         }
-        const body = (context.body instanceof FormData || isBlob(context.body))
+        const body = (context.body instanceof FormData || context.body instanceof URLSearchParams || isBlob(context.body))
 	    ? context.body
 	    : JSON.stringify(context.body);
 
diff --git a/samples/client/petstore/typescript-fetch/tests/default/mocks.ts b/samples/client/petstore/typescript-fetch/tests/default/mocks.ts
index c140489d8f72..9a3a3494ff81 100644
--- a/samples/client/petstore/typescript-fetch/tests/default/mocks.ts
+++ b/samples/client/petstore/typescript-fetch/tests/default/mocks.ts
@@ -1,5 +1,7 @@
 import * as FormData from 'form-data';
+import { URLSearchParams } from 'url';
 
 const globals = global as any;
 
 globals.FormData = FormData;
+globals.URLSearchParams = URLSearchParams;