Although considered as one of the most viable emerging non-volatile memory, the spin-transfer-torque magnetic random access memory (STT-MRAM) suffers from its weakness in the write operation. Spin-orbit torque magnetic random access memory (SOT-MRAM) has been recently proposed to provide lower write energy consumption. Nevertheless, additional write energy reduction is still on demand for embedded memory purposes. In this paper, we propose an early write termination (EWT) technique for SOT-MRAM, which can greatly reduce the write energy consumption by efficiently removing the unnecessarily long write pulse. The proposed Dynamic Reference Early Termination (DRET) scheme provides energy savings in all write operations while guaranteeing reliable operation. Simulation results using 65nm CMOS technology show that 76.6% of write energy can be saved on average compared to the conventional SOT-MRAM.