Revealing security vulnerabilities is one of great challenges for the Android ecosvstem Staticanalvsis is the usual approach of the securitv analysis for computer software However.it is undirected and time-consuming for the common static analvsis methods to analvze the entire Android application systematicallv from the main entry point In order to adapt to the event-driven feature of Android applications.a model guided securitv analysis approach for Android applications is introduced and implemented into the prototype tool MSAS This approach builds and utilizes the Operation Security Model to guide the targeted analysis process.and then concentrate on the identified analvsis surface to reduce analvsis workload.thereby achieving fast analysis speed and on-demand code coverage based on the securitv rules The test result shows that this approach can improve the efficiencv and effect of securitv analvsis for Android applications.and it has revealed ll securitv vulnerabilities by analvzing several popular Android applications.