The volatility and randomness of renewable energy have exacerbated the difficulty of evaluating static voltage stability in traditional power systems. In order to effectively account for the impact of wind power output uncertainty on static voltage stability assessment, first, the sensitivity of each node load margin to wind power injection power is derived through the power system load margin. Further, each order semi-invariant and each order moment of power system load margin are determined. Then, combining the various moments and semi-invariants of the injected power of the nodes connected to the wind power, the Gram-Charlier expansion of the various moments of the load margin is carried out. Thus the probability distribution of the load margin is obtained by taking into account the uncertainty of wind power to realize the probability assessment of the static voltage stability of the power system. Finally, the accuracy and effectiveness of the proposed method are verified by the IEEE30 node system. This work is supported by the Science and Technology Project of State Grid Liaoning Electric Power Co., Ltd. (No. 2018YF-25) and the Science and Technology Project of State Grid Corporation of China (No. SGTYHT17-JS-199).