Salt bath nitriding/nitrocarburizing is a surface treatment developed to improve tribological and corrosion properties of ferrous materials. In this research, sintered Astaloy CrM ® + 0.3% C samples were nitrocarburized at 580 °C for 1, 1.5, 2 and 2.5 h. The microstructure and phase composition of the surface layer was investigated by optical and scanning microscopy and X-ray diffraction. Corrosion behavior of samples was evaluated using both potentiodynamic polarization technique and electrochemical impedance spectroscopy in 3.5% sodium chloride solution. XRD analyses indicate that the surface layer in nitrocarburized samples is mainly composed of ɛ-iron carbonitride (Fe 2–3(CN)). The results reveal that salt bath nitrocarburizing for at least 2 h can improve significantly corrosion resistance of sintered Astaloy CrM ® + C.