In current cloud services, users put their data and resources into the cloud so as to enjoy the on-demand high quality applications and services. Different from the conventional services, users in cloud services lose control of their data which is instead manipulated by the large-scale cloud. Therefore, cloud service providers (CSP) guarantee that the cloud which they provide is of high confidence in accuracy and integrity. Traditional penetration test is carried out manually and has low efficiency. In this paper, we propose FPTC, a novel framework of penetration test in cloud environment. In FPTC, there are managers, executors and toolkits. FPTC managers guide FPTC executors to gather information from the cloud environment, generate appropriate testing scenarios, run matched tools in the toolkit and collect test results to do evaluation. The capacity and quality of the toolkit is a key issue in FPTC. We develop a prototype in which FPTC is implemented and the experimental results show that FPTC is helpful to automatically carry out penetration test in cloud environment.