As an important link in project management ,audit plays an important role in controlling investment and improving management.Along with the Popularizing and Implementing of ERP,how to carry out project audit under the information environment has become an important topic which urgent needs to study and explore.based on combining management mode of Power Grid project,project audit is classified into five types as settlement audit、accounts audit、internal control audit、business flow audit and performance audit in this paper。Then the paper studies how to carry out five types of audit under the information environment with the basic tool of ERP audit system which is developed by State Grid .