The detent force of the permanent magnet linear synchronous motor (PMLSM) is caused by the interaction between the permanent magnet and the iron core of the mover without input current. It is a function of the mover position relative to the stator. This paper proposes a control based method to reduce the detent force for the PMLSM. This detent force that can be predicted by finite element method (FEM) is compensated by injecting the instantaneous current using the field oriented control (FOC) method. Both the simulated and experimental results are reported to validate the effectiveness of this proposed method.