In order to cope with the large-scale changes of the sending grid tide and the voltage disturbance of the converter bus caused by the random fluctuation of wind power, which further leads to additional actions of the discrete equipment in the converter station, the coordinated secondary voltage control method of AC-DC system considering the randomness of wind power is proposed: firstly, the degree of wind power fluctuation is described by defining the relative deviation of power, and the characteristic time periods of wind power fluctuation cannot be ignored in the secondary voltage control are screened out; then the k -means clustering method to obtain typical scenarios of wind power output in the characteristic time period; finally, the probabilistic scenario method is used to represent the randomness of wind power, and the uncertainty optimization problem is solved with the help of the chance constraint method. Based on the modified IEEE39 node arithmetic system, simulations are performed and the effectiveness of the proposed method is verified.