Abstract. As a new technology in IT industry, cloud computing has been much focused by both academia and industry. And many topics in cloud computing are under study. However, as one of the most important issue, billing and pricing has been not so much concerned. In this paper, we propose a novel pay-peruse billing model that can be used for the applications in cloud computing. Built based on leasing instances, the model is put forward according to the analysis of the real applications in the cloud computing environment. That is, with the model, the users will be charged totally by the amount of the resources they have used. Simulation results show that the model is correct and feasible.