Informatization is the inevitable requirement of development. This paper takes the SMES of our country as an example. Facing to the new informatization way--cloud computing ERP financial management system, the SMES is in a bind in the informatization construction. This paper builds a system of enterprise information resource management based on clarifying the intrinsic quality of cloud computing ERP financial management system. Through this firm can gain the sharing resources, reduce the cost of enterprise information, transforming from traditional one to digital one, and improve the core competitiveness market competition.