Abstract: 18Cr2Ni4WA is an alloy carburizing steel commonly used in aviation. The stability of carburizing quality directly affects the reliability and service life of products. This paper introduces the process parameters at different carburizing layer depths of 18Cr2Ni4WA steel, including carburizing temperature, carburizing time and carbon potential. The result shows that the carburizing layer depth increases parabolic regularly, with the increase of the carburizing time. And the depths can be measured more quickly by metallographic examination after isothermal quenching.