Abstract: Tempering is an important mean of controlling residual stress. The precipitation behavior of 700L tempering carbide under different predeformation and external stress was studied by Gleeble thermal simulation experiment, nonisothermal double tempering experiment and SEM, TEM microstructure analysis. The results show that during the tempering process, applied stress can promote the nucleation and precipitation of carbides. When the applied load is zero, the carbides are mainly distributed in the grain boundaries, and the larger size is 13.9 nm.After 50 MPa and 100 MPa stress tempering, the number of carbides in the microstructure increase significantly, with sizes of 11.4 nm and 11.6 nm, respectively, and the precipitation position of carbides also change from grain boundaries to intragranular dispersion. In the stress range studied, increasing the pre-deformation before tempering can effectively increase the nucleation rate of the precipitates and reduce the average diameter of the precipitates. Under 0MPa, the carbide size of the tempered sample without deformation is 13.9 nm, while the carbide sizes of the 5% and 10% pre-deformed tempered samples are 12.9 nm and 11.5 nm, which are reduced by 7.2% and 17.2% compared with the undeformed samples.According to quantitative statistics, the volume fraction of precipitates is almost constant under different tempering processes.