Abstract: Taking Fe-1.8Ni-0.5Mo-1.2Cu-0.2C pre-alloy powder as raw material, a powder metallurgy gear was prepared by warm compaction, sintering, carburizing, quenching and low temperature tempering technologies. The microstructure and properties of the gear were studied by optical microscopy, scanning electron microscopy and hardness testing, etc. The results show that the warm compaction green density was 7.35 g·cm-3 and relative density was 94.2%. The microstructure of sintered gear mainly was pearlite and ferrite, the hardness, density, relative density of the sintered gear was 46-54 HRA, 7.37 g·cm-3 and 94.5%, respectively. The slight shrinkage of sintered gear was found, but it still kept good dimensional stability. The microstructure of carburized layer after heat treatment mainly was tempered martensite and small amounts of retained austenite, and the teeth mechanical resistance was 9.6 kN and the hardness was increased to 66-75 HRA.