Abstract: The poor thermal conductivity of high manganese steel leads to a slow cooling rate in the center of the frog during quenching,making it easy to produce excessive carbides in the center.The microstructure and temperature variation of high manganese steel during cooling process were analyzed by thermal simulation test and finite element numerical simulation.The results of thermal simulation test showed that with the increase of cooling rate,the precipitated carbides of high manganese steel gradually decreased.At the cooling rate of 5℃/s,the level of precipitated carbides was X2 grade.According to the finite element simulation results,the cooling equipment was improved,and the cooling rate of the improved high manganese steel core reached 5℃/s.The level of precipitated carbides in the core of high manganese steel was increased from X3 to X2,and the mechanical properties were improved,thus improving the product quality of high manganese steel frog.