The invention discloses a power distribution network state estimation method based on APSO-BP. The method comprises the following steps of: S1: calling power distribution network state data; S2: establishing a time sequence correlation data model; S3: constructing an APSO-BP network model; and S4: outputting a power distribution network state estimation result. The power distribution network statedata comprise power distribution network historical data and power distribution network real-time measurement data, power distribution network operation information and line tidal volume measurementinformation which are respectively obtained from a historical database, and branch power measurement data information which is obtained from a real-time measurement database, and a pseudo measurementmodel is established. By adopting the technical scheme, the voltage amplitude and the phase angle of a power distribution station area can be effectively estimated, voltage offset data support can beprovided for the comprehensive evaluation index of the power distribution station area, and an effective reference voltage boundary is provided for operation risk pre-judgment, power sharing scheduling and related decision making.