Abstract: In this paper, annealing microstructure of three types of Cr13 corrosion resistant plastic die steel were researched, contrast and analysis of six different heat treatment process, in order to get homogeneous pearlite spheroidization microstructure. The results show that, the best spheroidizing annealing process of 420MOD steel was isothermal annealing of 830℃+760℃, the best spheroidizing annealing process of 1.2083 steel was quenching of 960℃ add isothermal annealing of 830℃+760℃, the best spheroidizing annealing process of FT64 steel was quenching of 960℃ add annealing of 870℃. 420MOD and 1.2083steel should avoid preservation period of about 870℃,to form lamellar pearlite and chain microstructure at this stage. The quenching process before FT64 steel annealing could eliminate banding distribution of secondary carbides.