diff --git a/lib/sandbox/postman-legacy-interface.js b/lib/sandbox/postman-legacy-interface.js
index d718d898..5dd38aaf 100644
--- a/lib/sandbox/postman-legacy-interface.js
+++ b/lib/sandbox/postman-legacy-interface.js
@@ -61,6 +61,19 @@ const _ = require('lodash'),
         URLENCODED: 'urlencoded',
         FORMDATA: 'formdata',
         FILE: 'file'
+    },
+
+    /**
+     * Proxy handler for response headers to make them case-insensitive.
+     */
+    responseHeadersProxyHandler = {
+        get: (target, key) => {
+            if (key === 'hasOwnProperty') {
+                return (prop) => { return Reflect.has(target, prop.toLowerCase()); };
+            }
+
+            return target[key.toLowerCase()];
+        }
     };
 
 function getRequestBody (request) {
@@ -376,15 +389,18 @@ module.exports = {
             globalvars.responseCookies = execution.cookies || [];
 
             /**
-             * Stores the response headers with the keys being case sensitive
+             * Stores the response headers with case insensitive keys
              *
              * @memberOf SandboxGlobals
              * @type {Array.<Object>}
              */
-            globalvars.responseHeaders = {};
+
+            const responseHeaders = {};
+
             execution.response && execution.response.headers.each(function (header) {
-                header && !header.disabled && (globalvars.responseHeaders[header.key] = header.value);
+                header && !header.disabled && (responseHeaders[header.key.toLowerCase()] = header.value);
             });
+            globalvars.responseHeaders = new Proxy(responseHeaders, responseHeadersProxyHandler);
 
             /**
              * @memberOf SandboxGlobals