In the present investigation, AISI 304 austenitic stainless steel was low temperature plasma carburized at 460 °C using gaseous acetone. Optical Microscopic observation (OM) and x-ray diffraction analysis (XRD) technology were used to characterize the microstructure and phase composition of the carburized layers. The hardness of the carburized layer was tested by microhardness tester. The corrosion behaviors of the carburized layers, especially the inner layers, were preliminary characterized based on the potentiodynamic polarization curve and electrochemical impedance spectroscopy (EIS). The experimental results show that after plasma carburizing, typical microstructure with ‘three layers’ characteristics was formed on stainless steel surface, i.e. the thin topmost layer, the top ‘grey layer’ and the inner ‘white layer’. The phases on the surface layer are mainly of the carbon ‘expanded’ austenite (γC), the carbon ‘expanded’ martensite (αC) and a trace of Fe3C phases. The surface hardness of the carburized stainless steel can be up to 933 HV0.1, which is about 5 times higher than that of the untreated one. For the stainless steel specimen plasma carburized for 8 h, the corrosion resistances of the topmost layer and the ‘white layer’ are better than that of the ‘grey layer’ under the present corrosion test conditions.