For this study, a new temperature prediction analytical model for Inconel 718 milling is presented with the consideration of microstructure evolution while accounting for the effects of dynamic recrystallization. The milling condition is transferred to equivalent orthogonal cutting condition at each rotation angle. The previous constant yield stress term in Johnson-Cook constitutive equation is replaced by a grain size-dependent term. The grain size is calculated according to dynamic recrystallization, a strain and temperature induced recrystallization process, through the recrystallized volume fraction by Johnson-Mehl-Avrami-Kolmogorov model. The temperature rise is due to the flow stress in shear zone considered as primary heat source and the secondary rubbing heat source between the tool tip and machined surface. The heat source density is calculated based on the cutting forces predicted from flow stress. The predicted temperature field is validated by numerical model in six cases and experimental measurements in ten cases from two papers, and improvements are observed through the comparison between proposed and conventional models.