Abstract: Hot rolled 430 ferritic stainless steel was annealed at different temperatures and holding time. The effects of different annealing treatments on the microstructure and mechanical properties of 430 ferrite stainless steel were studied by metallographic microscope, scanning electron microscope, universal testing machine and so on. The results show that the microstructure of annealed 430 stainless steel is composed of ferrite and black precipitated phase. With the increase of annealing temperature and holding time, the ferrite grain size of 430 stainless steel decreases first and then increases, and the amount of precipitated phase decreases first and then increases. The microstructure of 430 stainless steel with annealing temperature of 850 ℃ for 10 min insulation is fine and uniform, the amount of precipitated phase is the least, the tensile strength is 663.3 MPa, the elongation is 32.4%, the strong plasticity match is good. Therefore, 850 ℃ annealing insulation for 10 min is ideal annealing process for 430 ferric stainless steel.