Abstract: The relationship of deformation resistance,degree and rate was studied by means of Gleeble-2000 thermal simulator.The effect of heating temperature on austenitic grain size was analyzed.The micro alloy element niobium or/and vanadium would distinctly enhance the deformation resistance of the high strength micro alloy(HSMA) steel at high temperature,which would be benefit for controlling the rolling and cooling of HSMA steel.The more the micro alloy element in the HSMA steel or the higher the tensile strength of the HSMA steel,the more sensitive to deformationin resistance under a big deformation degree during cooling process.