diff --git a/modules/swagger-codegen/src/main/resources/Javascript/ApiClient.mustache b/modules/swagger-codegen/src/main/resources/Javascript/ApiClient.mustache
index 934201a0404..d85705f5127 100644
--- a/modules/swagger-codegen/src/main/resources/Javascript/ApiClient.mustache
+++ b/modules/swagger-codegen/src/main/resources/Javascript/ApiClient.mustache
@@ -317,7 +317,7 @@
     // Rely on SuperAgent for parsing response body.
     // See http://visionmedia.github.io/superagent/#parsing-response-bodies
     var data = response.body;
-    if (data == null || !Object.keys(data).length) {
+    if (data == null || (typeof data === 'object' && typeof data.length === 'undefined' && !Object.keys(data).length)) {
       // SuperAgent does not always produce a body; use the unparsed response as a fallback
       data = response.text;
     }
diff --git a/samples/client/petstore/javascript-promise/src/ApiClient.js b/samples/client/petstore/javascript-promise/src/ApiClient.js
index 433f6b1a445..3f735978306 100644
--- a/samples/client/petstore/javascript-promise/src/ApiClient.js
+++ b/samples/client/petstore/javascript-promise/src/ApiClient.js
@@ -320,7 +320,7 @@
     // Rely on SuperAgent for parsing response body.
     // See http://visionmedia.github.io/superagent/#parsing-response-bodies
     var data = response.body;
-    if (data == null || !Object.keys(data).length) {
+    if (data == null || (typeof data === 'object' && typeof data.length === 'undefined' && !Object.keys(data).length)) {
       // SuperAgent does not always produce a body; use the unparsed response as a fallback
       data = response.text;
     }
diff --git a/samples/client/petstore/javascript/src/ApiClient.js b/samples/client/petstore/javascript/src/ApiClient.js
index 96fccb169e1..6d150160192 100644
--- a/samples/client/petstore/javascript/src/ApiClient.js
+++ b/samples/client/petstore/javascript/src/ApiClient.js
@@ -320,7 +320,7 @@
     // Rely on SuperAgent for parsing response body.
     // See http://visionmedia.github.io/superagent/#parsing-response-bodies
     var data = response.body;
-    if (data == null || !Object.keys(data).length) {
+    if (data == null || (typeof data === 'object' && typeof data.length === 'undefined' && !Object.keys(data).length)) {
       // SuperAgent does not always produce a body; use the unparsed response as a fallback
       data = response.text;
     }