First, the scope of application is different. The examination and approval system only applies to government investment projects; The approval system is applicable to major projects and restricted projects invested and constructed by enterprises with non-government funds; The filing system is suitable for small and medium-sized projects invested by enterprises.

Second, the contents of the audit are different. In the past, the examination and approval system was an all-round examination and approval of investment projects, while the examination and approval system was only the government's examination and approval from the perspective of social and economic management, and it was not responsible for considering the market prospects, sources of funds, economic benefits and other factors of enterprise investment projects.

Third, the procedures are different. In the past, the approval system generally went through many links such as project proposal, feasibility study report and preliminary design, while the approval system and filing system only had one link of project application approval or filing.