Massive multivariate heterogeneous smart grid data are compressed and stored without processing, which has the problems of large compression error and long running time, affecting the compression and storage effect. Therefore, a data compression and storage method of massive multivariate heterogeneous smart grid based on state estimation is proposed. The massive multivariate heterogeneous smart grid data are integrated to deduce the accurate smart grid data. And the massive multivariate heterogeneous smart grid data are compressed through the Tucker decomposition smart grid big data compression method. Extensible markup language (XML) technology is used to preprocess the data, and combined with the nonrelational database technology to realize the rapid storage of massive multivariate heterogeneous smart grid data. The experimental results show that this method has high accuracy in estimating the dynamic parameters of line resistance and reactance, low average absolute error and Fnorm error of data compression, short running time and certain practical application performance.