The invention discloses a voltage stability discrimination method for a DC receiving end AC system based on WAMS (Wide Area Measurement System) dynamic tracking. The method is characterized by comprising the following steps of: calculating the voltage stability level of a receiving system of an AC system in the normal operation mode of the AC system; calculating the voltage stability level of the receiving system of the AC system under the line fault disconnection condition; sorting line faults; combining a worst cascading fault set; calculating the voltage stability level of the receiving end AC system under the cascading fault condition; and judging whether the voltage instability occurs or not. The voltage stability discrimination method provided by the invention has the advantages of performing the characteristic analysis of the transient voltage instability accidents existing in existing and planned AC / DC hybrid power grids, providing effective fault screening and sorting according to the degree of damage caused by the AC fault to the stable operation of the DC system, reasonably establishing the cascading fault set by combining a power flow transferring condition after faults, and quickly assessing the grid voltage instability risk of the receiving end of the DC system after faults.