The present invention discloses an electric power system alternating current network subband equivalent method based on port impedance zero-pole matching. The method comprises the steps of: measuringimpedance-frequency features of a port of a network to be equivalent, and obtaining a zero pole; taking each zero point as a boundary, cutting a frequency shaft into a plurality of frequency bands, oneach frequency band, taking each pole as one 'frequency point of special concern', respectively calculating RLC parameters of equivalent circuits on different frequency bands according to a specificcalculation method, and obtaining each corresponding equivalent circuit. Therefore, simplified equivalence of a network is achieved, an electric power system transient simulation analysis speed is increased, and a calculated amount is reduced.