GUI testing is a very important part of software testing. However, the research of GUI testing is far from being extensively performed. With analyses of GUI test case generation based on AI planning, a new generation of Weight-based automatic GUI test cases is provided. It introduces a conception of weighted event, and uses the conception to separate the events into subsets according to the importance of GUI. Then it determines the order to generate test cases in different subsets. With more reasonable test cases generated, it makes the GUI testing more efficient. The results of experiment show that more errors are detected applying this new method under the identical number of test cases.