The hot deformation behaviors of a novel Cr + N alloyed high-Mn austenitic steel, namely 60Mn18Cr7N steel, and a traditional one, namely 120Mn13 steel, were comparatively investigated at a temperature range of 1173–1473 K and strain rate range of 0.001–1 s−1 using a single-pass hot compression test. The results indicate that the presence of additional alloying elements in the 60Mn18Cr7N steel leading to a higher flow stress during hot deformation. To better understand the hot deformation behavior and determine the optimal forging treatment region, constitutive models based on the Arrhenius equation and processing maps utilizing strain rate sensitivity (m) were employed. The deformation activation energy of the 60Mn18Cr7N steel was found to be significantly higher than that of the 120Mn13 steel. By analyzing the deformation microstructure and processing map, the optimal processing domain for the 120Mn13 steel was identified within a temperature range of 1373–1473 K and strain rate range of 0.1–1 s−1, while higher temperature or strain was required for the 60Mn18Cr7N steel to achieve significant recrystallization.