Future smart grid will face the problems to be solved such as leaking user’s privacy, encrypting grid sensitive data,etc while providing users with a two-way interactive, high reliability, high-quality electricity service. This paper derives data security threat to the grid on several factors-the ciphertext data access, sensitive data acquisition and integrity data test problems after analyzing the structure and characteristics of current grid data.Secondly,discuss several current data encryption technology-symmetric,asymmetric encryption, properties granularity encryption, after the demonstration of its good performance in the protection of data privacy security, also find many bottlenecks in data processing by central server such as the server side can not compare or devide different types of data, and can not achieve the projection operation either, multi-table query generates a lot of pseudo-connections. Taking the drawbacks of the programs mentioned above, We propose the data polymerization strategy based blind signature,finally solve the above problems through the experimental results of this strategy and achieve the protection mechanisms including anonymity,addition,non-addition supported,proves the feasibility of this strategy in ensuring the data security for smart grid.