When traditional sliding-mode flux observer (SMO) is used to observe the flux linkage of interior permanent magnet synchronous motor（IPMSM）,it is prone to occur observation errors due to parameter changes.To overcome the problem, taking stator current as state equation,an adaptive super-twisting sliding-mode observer (STA-SMO) was constructed.The permanent magnet flux linkage was reconstructed based on the sliding-mode equivalent theory to realize the online identification of the permanent magnet flux linkage.The adaptive law of stator resistance was derived through Lyapunov function.The results show that compared with traditional SMO,the adaptive STA-SMO overcomes the influence of resistance parameter changes on flux observation,and effectively suppresses chattering and improves identification accuracy.