GUI Test Case Prioritization by State-Coverage Criterion Graphical User Interface (GUI) application is a kind of typical event-driven software (EDS) that transforms state according to input events invoked through a user interface. It is time consuming to test a GUI application since there are a large number of possible event sequences generated by the permutations and combinations of user operations. Although some GUI test case prioritization techniques have been proposed to determine “which test case to execute next” for early fault detection, most of them use random ordering to break tie cases, which has been proved to be ineffective. Recent research presents the opinion that using hybrid criteria can be an effective way for tie-breaking, but few studies focus on seeking a new criterion cooperating well with other criteria when breaking tie cases. In this paper, we propose a state-distance-based method using state coverage as a new criterion to prioritize GUI test cases. An empirical study on three GUI programs reveals that the state-distance-based method is really suitable for GUI test case prioritization and can cooperate well with the (additional) event length criterion.