In order to meet the operational requirements of target assignment for multi-platform anti-ship missiles in coordinated sea assault, a target assignment model for multi-platform anti-ship missiles is established based on the analysis of the constraints and performance indicators of target assignment. Aiming At the problems of low efficiency and easy to fall into local optimal solution in traditional target assignment methods, the standard genetic algorithm (SGA) is improved to adjust the crossover and mutation probability adaptively, and a multi-platform target assignment algorithm based on improved genetic algorithm is proposed. The simulation analysis is carried out in two different combat scenarios. The simulation results show that compared with the standard genetic algorithm, the convergence speed of the improved algorithm is improved. At the same time, the obtained target assignment scheme is reasonable and effective, and meets the constraints, which can provide a reference for the target assignment in cooperative operations.