Abstract: The fractional order model reference adaptive system (FOMRAS) is under direct force control (DFC) of permanent magnet linear synchronous motor (PMLSM), which has large speed estimation error, slow response speed and poor anti-interference capability. To solve this problem, an improved FOMRAS algorithm is proposed, which adopts an improved fractional order adaptive law to track the speed in speed identification. It reduced the jitter of thrust response and ensured that the estimated value approached the real value quickly. It was applied to DFC, and the speed sensor-less control was realized. The simulation results show that the speed sensor-less PMLSM-DFC with improved FOMRAS has obviously enhanced anti-disturbance ability, good dynamic and static ability and ensured the stability of the system.