A physical and mathematical model is proposed for describing the nitrogen launching system (NLS) based on the dynamics of pneumatics and mechanisms,and a digital simulation program is developed to analyze the dynamic performance of NLS.The multi-objective optimization for the pitching angle and velocity of missiles is proposed for the first time.Singularity detection in wavelet analysis is conducted to find the optimum iteration point of system optimization.The sequence unconstrained minimization technology based on wavelet and complex methods are compared to show that the former is better for optimal designs.And the optimization results agree well with the experimental ones.