The sintering behavior of 17-4PH stainless steel feedstock for metal injection molding was investigated in the temperature range of 650–1050 °C. Effects of sintering conditions, such as sintering temperature and sintering atmosphere, were examined. Results showed that when sintered in the hydrogen/nitrogen atmosphere, the 17-4PH feedstock was oxidized over the temperature range of investigation. The degree of oxidization increased with the sintering temperature. The main oxidization product was Cr 2 O 3 as revealed by X-ray diffraction and composition analysis. The oxidation can be avoided by sintering in vacuum or argon atmosphere.