diff --git a/CHANGES.md b/CHANGES.md
index 7848cdd3fb3e..e1bde72eb300 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -13,6 +13,7 @@ Change Log
 * Fixed translucency bug for certain material types [#5335](https://github.com/AnalyticalGraphicsInc/cesium/pull/5335)
 * Fix picking polylines that use a depth fail appearance. [#5337](https://github.com/AnalyticalGraphicsInc/cesium/pull/5337)
 * Fixed a crash when morphing from Columbus view to 3D. [#5311](https://github.com/AnalyticalGraphicsInc/cesium/issues/5311)
+* Fixed a bug which prevented KML descriptions with relative paths from loading. [#5352](https://github.com/AnalyticalGraphicsInc/cesium/pull/5352)
 * Updated documentation for Quaternion.fromHeadingPitchRoll [#5264](https://github.com/AnalyticalGraphicsInc/cesium/issues/5264)
 
 ### 1.33 - 2017-05-01
diff --git a/Source/DataSources/KmlDataSource.js b/Source/DataSources/KmlDataSource.js
index 0807ee87b7bd..87f00c7f7a35 100644
--- a/Source/DataSources/KmlDataSource.js
+++ b/Source/DataSources/KmlDataSource.js
@@ -253,7 +253,7 @@ define([
         });
     }
 
-    function replaceAttributes(div, elementType, attributeName, uriResolver) {
+    function embedDataUris(div, elementType, attributeName, uriResolver) {
         var keys = uriResolver.keys;
         var baseUri = new Uri('.');
         var elements = div.querySelectorAll(elementType);
@@ -272,6 +272,16 @@ define([
         }
     }
 
+    function applyBasePath(div, elementType, attributeName, proxy, sourceUri) {
+        var elements = div.querySelectorAll(elementType);
+        for (var i = 0; i < elements.length; i++) {
+            var element = elements[i];
+            var value = element.getAttribute(attributeName);
+            var uri = resolveHref(value, proxy, sourceUri);
+            element.setAttribute(attributeName, uri);
+        }
+    }
+
     function proxyUrl(url, proxy) {
         if (defined(proxy)) {
             if (new Uri(url).isAbsolute()) {
@@ -1431,7 +1441,7 @@ define([
 
     var scratchDiv = document.createElement('div');
 
-    function processDescription(node, entity, styleEntity, uriResolver) {
+    function processDescription(node, entity, styleEntity, uriResolver, proxy, sourceUri) {
         var i;
         var key;
         var keys;
@@ -1516,10 +1526,14 @@ define([
 
         //Rewrite any KMZ embedded urls
         if (defined(uriResolver) && uriResolver.keys.length > 1) {
-            replaceAttributes(scratchDiv, 'a', 'href', uriResolver);
-            replaceAttributes(scratchDiv, 'img', 'src', uriResolver);
+            embedDataUris(scratchDiv, 'a', 'href', uriResolver);
+            embedDataUris(scratchDiv, 'img', 'src', uriResolver);
         }
 
+        //Make relative urls absolute using the sourceUri
+        applyBasePath(scratchDiv, 'a', 'href', proxy, sourceUri);
+        applyBasePath(scratchDiv, 'img', 'src', proxy, sourceUri);
+
         var tmp = '<div class="cesium-infoBox-description-lighter" style="';
         tmp += 'overflow:auto;';
         tmp += 'word-wrap:break-word;';
@@ -1582,7 +1596,7 @@ define([
         kmlData.snippet = queryStringValue(featureNode, 'Snippet', namespaces.kml);
 
         processExtendedData(featureNode, entity);
-        processDescription(featureNode, entity, styleEntity, uriResolver);
+        processDescription(featureNode, entity, styleEntity, uriResolver, dataSource._proxy, sourceUri);
 
         if (defined(queryFirstNode(featureNode, 'Camera', namespaces.kml))) {
             console.log('KML - Unsupported view: Camera');
diff --git a/Specs/DataSources/KmlDataSourceSpec.js b/Specs/DataSources/KmlDataSourceSpec.js
index dcba41357518..350d5f57b74d 100644
--- a/Specs/DataSources/KmlDataSourceSpec.js
+++ b/Specs/DataSources/KmlDataSourceSpec.js
@@ -1832,6 +1832,28 @@ defineSuite([
         });
     });
 
+    it('BalloonStyle: relative description paths absolute to sourceUri', function() {
+        var kml = '<?xml version="1.0" encoding="UTF-8"?>\
+        <Placemark>\
+            <description><![CDATA[<img src="foo/bar.png"/>]]></description>\
+        </Placemark>';
+
+        return KmlDataSource.load(parser.parseFromString(kml, "text/xml"), {
+            camera : options.camera,
+            canvas : options.canvas,
+            sourceUri : 'http://test.invalid'
+        }).then(function(dataSource) {
+            var entity = dataSource.entities.values[0];
+
+            var element = document.createElement('div');
+            element.innerHTML = entity.description.getValue();
+
+            var a = element.firstChild.firstChild;
+            expect(a.localName).toEqual('img');
+            expect(a.getAttribute('src')).toEqual('http://test.invalid/foo/bar.png');
+        });
+    });
+
     it('BalloonStyle: description retargets existing links to _blank', function() {
         var kml = '<?xml version="1.0" encoding="UTF-8"?>\
         <Placemark>\