diff --git a/modules/swagger-codegen/src/main/resources/TypeScript-node/api.mustache b/modules/swagger-codegen/src/main/resources/TypeScript-node/api.mustache
index 6e7ef1c19f3..bf6b76d6b41 100644
--- a/modules/swagger-codegen/src/main/resources/TypeScript-node/api.mustache
+++ b/modules/swagger-codegen/src/main/resources/TypeScript-node/api.mustache
@@ -190,9 +190,9 @@ export class {{classname}} {
         let formParams: any = {};
 
 {{#allParams}}{{#required}}
-        // verify required parameter '{{paramName}}' is set
-        if (!{{paramName}}) {
-            throw new Error('Missing required parameter {{paramName}} when calling {{nickname}}');
+        // verify required parameter '{{paramName}}' is not null or undefined
+        if ({{paramName}} === null || {{paramName}} === undefined) {
+            throw new Error('Required parameter {{paramName}} was null or undefined when calling {{nickname}}.');
         }
 {{/required}}{{/allParams}}
 {{#queryParams}}
diff --git a/samples/client/petstore/typescript-node/api.ts b/samples/client/petstore/typescript-node/api.ts
index c7449aeb5ec..1e314a3fc64 100644
--- a/samples/client/petstore/typescript-node/api.ts
+++ b/samples/client/petstore/typescript-node/api.ts
@@ -368,9 +368,9 @@ export class PetApi {
         let formParams: any = {};
 
 
-        // verify required parameter 'petId' is set
-        if (!petId) {
-            throw new Error('Missing required parameter petId when calling deletePet');
+        // verify required parameter 'petId' is not null or undefined
+        if (petId === null || petId === undefined) {
+            throw new Error('Required parameter petId was null or undefined when calling deletePet.');
         }
 
         headerParams['api_key'] = apiKey;
@@ -534,9 +534,9 @@ export class PetApi {
         let formParams: any = {};
 
 
-        // verify required parameter 'petId' is set
-        if (!petId) {
-            throw new Error('Missing required parameter petId when calling getPetById');
+        // verify required parameter 'petId' is not null or undefined
+        if (petId === null || petId === undefined) {
+            throw new Error('Required parameter petId was null or undefined when calling getPetById.');
         }
 
         let useFormData = false;
@@ -592,9 +592,9 @@ export class PetApi {
         let formParams: any = {};
 
 
-        // verify required parameter 'petId' is set
-        if (!petId) {
-            throw new Error('Missing required parameter petId when calling getPetByIdInObject');
+        // verify required parameter 'petId' is not null or undefined
+        if (petId === null || petId === undefined) {
+            throw new Error('Required parameter petId was null or undefined when calling getPetByIdInObject.');
         }
 
         let useFormData = false;
@@ -650,9 +650,9 @@ export class PetApi {
         let formParams: any = {};
 
 
-        // verify required parameter 'petId' is set
-        if (!petId) {
-            throw new Error('Missing required parameter petId when calling petPetIdtestingByteArraytrueGet');
+        // verify required parameter 'petId' is not null or undefined
+        if (petId === null || petId === undefined) {
+            throw new Error('Required parameter petId was null or undefined when calling petPetIdtestingByteArraytrueGet.');
         }
 
         let useFormData = false;
@@ -761,9 +761,9 @@ export class PetApi {
         let formParams: any = {};
 
 
-        // verify required parameter 'petId' is set
-        if (!petId) {
-            throw new Error('Missing required parameter petId when calling updatePetWithForm');
+        // verify required parameter 'petId' is not null or undefined
+        if (petId === null || petId === undefined) {
+            throw new Error('Required parameter petId was null or undefined when calling updatePetWithForm.');
         }
 
         let useFormData = false;
@@ -827,9 +827,9 @@ export class PetApi {
         let formParams: any = {};
 
 
-        // verify required parameter 'petId' is set
-        if (!petId) {
-            throw new Error('Missing required parameter petId when calling uploadFile');
+        // verify required parameter 'petId' is not null or undefined
+        if (petId === null || petId === undefined) {
+            throw new Error('Required parameter petId was null or undefined when calling uploadFile.');
         }
 
         let useFormData = false;
@@ -955,9 +955,9 @@ export class StoreApi {
         let formParams: any = {};
 
 
-        // verify required parameter 'orderId' is set
-        if (!orderId) {
-            throw new Error('Missing required parameter orderId when calling deleteOrder');
+        // verify required parameter 'orderId' is not null or undefined
+        if (orderId === null || orderId === undefined) {
+            throw new Error('Required parameter orderId was null or undefined when calling deleteOrder.');
         }
 
         let useFormData = false;
@@ -1163,9 +1163,9 @@ export class StoreApi {
         let formParams: any = {};
 
 
-        // verify required parameter 'orderId' is set
-        if (!orderId) {
-            throw new Error('Missing required parameter orderId when calling getOrderById');
+        // verify required parameter 'orderId' is not null or undefined
+        if (orderId === null || orderId === undefined) {
+            throw new Error('Required parameter orderId was null or undefined when calling getOrderById.');
         }
 
         let useFormData = false;
@@ -1484,9 +1484,9 @@ export class UserApi {
         let formParams: any = {};
 
 
-        // verify required parameter 'username' is set
-        if (!username) {
-            throw new Error('Missing required parameter username when calling deleteUser');
+        // verify required parameter 'username' is not null or undefined
+        if (username === null || username === undefined) {
+            throw new Error('Required parameter username was null or undefined when calling deleteUser.');
         }
 
         let useFormData = false;
@@ -1540,9 +1540,9 @@ export class UserApi {
         let formParams: any = {};
 
 
-        // verify required parameter 'username' is set
-        if (!username) {
-            throw new Error('Missing required parameter username when calling getUserByName');
+        // verify required parameter 'username' is not null or undefined
+        if (username === null || username === undefined) {
+            throw new Error('Required parameter username was null or undefined when calling getUserByName.');
         }
 
         let useFormData = false;
@@ -1699,9 +1699,9 @@ export class UserApi {
         let formParams: any = {};
 
 
-        // verify required parameter 'username' is set
-        if (!username) {
-            throw new Error('Missing required parameter username when calling updateUser');
+        // verify required parameter 'username' is not null or undefined
+        if (username === null || username === undefined) {
+            throw new Error('Required parameter username was null or undefined when calling updateUser.');
         }
 
         let useFormData = false;