As for the optimization design of phase-coded signal sets of MIMO radar,an improved Sine- Cosine Algorithm (SCA) is proposed.Through the introduction of Lévy flight,the algorithm expands the search range for the position of target points to prevent partial optimization.The algorithm sets the control parameters,improves the convergence rate,and balances the global search and local search ability.Based on the Particle Swarm Optimization (PSO) weight theory,the adaptive updating equation is changed to improve the convergence precision,so as to obtain the best result.Based on the improved SCA,a phase-coded signal set of MIMO radar is designed with good correlation performance,and the convergence rate and convergence precision are obviously improved.