Fe-Cr-Mn-based stainless steel alloy powder was prepared by mechanical alloying method, which is induced by high energy milling. The milled powders were respectively annealed and sintered via hot pressing sintering method, and the phases evolution, microstructure and corrosion resistance were respectively analysed. It is found that the Fe-Cr-Mn-based stainless steel alloy prepared by mechanical alloying is mainly composed of metastable nanocrystalline ferrite phase. After annealing or hot pressing sintering, ferrite phase will transform into austenite phase, and the transformation temperature range from 650 °C to 700 °C. The powder milled for 16 h is hot pressed at 900 °C and 200 MPa for 1 h for bulk alloy. The average grain size of pressed bulk alloy is submicron, which displays high hardness and good corrosion resistance. The hardness, polarization voltage and polarization current are respectively 535 HV, -0.28 V and 1.43×10_^-9 A.cm_^-2.