Facilitating localization of code defect of an application includes receiving a set of element-value pairs generated by running the application with a test case. Further differences are identified between the set of element-value pairs and a baseline data result for the test case. Tree maps associated with respective elements are displayed in the set of element-value pairs, each of the tree maps representing relationship of code entities of the application related to its associated element, wherein one or more of the tree maps are marked out to show the differences thereby identifying potential defective codes of the application that have caused the differences.