Abstract: 50CrVA steel was subjected to different temperatures quenching and subsequent tempering of 450 ℃, the effects of quenching temperature on microstructure and mechanical properties of 50CrVA steel were investigated by microstructure observation, tensile test and impact test. The results show that all microstructure of 50CrVA steel is tempered troostite after quenching at 860-940 ℃and tempering at 450 ℃. At quenching temperature range of 860-940 ℃, the yield strength, tensile strength and elongation of 50CrVA steel all first increase and then decrease, and they achieve maximum value at quenching temperature of 920 ℃, while the impact energy shows the opposite trend.When quenching temperature is 920 ℃and tempering temperature is 450 ℃, 50CrVA steel has the best comprehensive mechanical properties, and the yield strength, tensile strength, elongation and impact energy are 1417 MPa, 1535 MPa, 12.2%and 21 J, respectively.