In order to improve the emission efficiency, a new drive coil structure is proposed by adding a magnetic conductor to change the magnetic field configuration. Based on the analysis of the influence of the magnetic field distribution of the driving coil on the launcher performance, the magnetic field configuration of the driving coil is optimized, and the influence of the structural parameters of the magnetic conductor on the magnetic field configuration is analyzed. The results show that the method can reduce the magnetic field leakage and inter-stage coupling, increase the axial gradient of the magnetic field inside the coil and the magnetic field force of the transmitting component, improve the energy conversion efficiency of the electromagnetic coil launcher, and obtain the optimal value of structural parameters of the magnetic conductor.