In order to optimize the structural parameters of the single-stage direct fed coil launcher and the energy distribution of the three-stage direct fed coil launcher, a field path coupling mathematical model and finite element analysis model of the three-stage direct fed coil launcher are established. The accuracy of the two models is calculated by adopting numerical calculation methods and finite element analysis methods. The results show that the motion data and circuit data calculated by the two models are basically consistent, proving that the two models have high accuracy. Based on the established parameterized model of the 3-level direct fed coil launcher, the differential evolution algorithm is used to optimize the structural parameters of the single-stage direct fed coil launcher and the energy allocation of the 3-level direct fed coil launcher. The results show that the iterative process is good at convergence with convergence being 60 iterations for single-stage optimization and 100 iterations for 3-level optimization. The optimization being over, the single-stage outlet speed increases from 27.5 m/s to 30.8 m/s with an output efficiency being improvement of 6%. The peak single-stage current decreases from 19 kA to 8 kA with a decrease of 57.9%. The 3-stage outlet speed increases from 56.4 m/s to 60.4 m/s with an output efficiency being improvement of 5%. The peak 3-stage current decreases from 25 kA to 10 kA with a decrease of 60%. The result show that the differential evolution algorithm has a good ability to optimize for multi-dimensional optimization problems of direct fed coil launchers.