Three warm-rolled ferrite/pearlite microstructures were prepared by rolling at 500℃, and the austenitizing characteristics were discussed in conjunction with deformation during the heating stage. The results indicated that the final austenite grain size was sensitive to the deformation direction of the initial warm-rolled microstructure. The transient microstructure at a given temperature was the most important influencing factor on the austenitizing characteristic combined with deformation. Moreover, the hot-rolled microstructure also had to be prepared in an optimal state because of its direct effect on the warm-rolled microstructure. Three warm-rolled ferrite / pearlite microstructures were prepared by rolling at 500 ° C, and the austenitizing characteristics were discussed in conjunction with deformation during the heating stage. The results indicated that the final austenite grain size was sensitive to the deformation direction of the initial warm -rolled microstructure. A transient temperature of the most important influencing factor on the austenitizing characteristic of the warm- rolled microstructure.