To guarantee in the case of constant power, as far as possible to reduce the internal ballistic process of maximum bore pressure, based on the NSGA-Ⅱ, CMOPSO, NSGA-Ⅲ multi-objective interior ballistic optimization algorithm, calculation and analysis for its. Taking a certain recoilless launch system as the research object, design variables and objective function were selected, the objective function was dimensionless, and the internal trajectory was optimized with multiple objectives, and the advantages and disadvantages of the three algorithms were compared. The results show that the CMPSO algorithm has the largest relative velocity distribution, and the NSGA-Ⅱ has a maximum relative pressure span, and the NSGA-Ⅲ also has the best convergence.