Abstract:A study strategy of hybrid state estimation for power system based on twostage linear iteration and basic principles of Kalman filter and linear iteration was proposed, it is designed to solve the problems of lower accuracy of power system mixed state estimation, poorer filtering effect and weaker convergence ability, etc. In the first stage, the measurement data of phasor measurement unit (PMU) were used for linear estimation. In the second stage, where the content of the first stage was combined with the traditional measurement value to estimate the state, and the high frequency characteristic of PMU was used to sample the twostage measurement data iteratively. Which was tested in IEEE 14 and IEEE 57 bus test system, and the results were compared with other hybrid models. The results showed that the estimation accuracy, data convergence and measurement parameter error of this strategy were better than those of other hybrid models.