Abstract: Based on a two-phase four-poles air-core compulsator, the discharge pulse shape optimization problem is studied. The characteristics of three typical kinds of loads for compulsator: electromagnetic rail guns, flashlamps and electro-thermal chemical guns are analyzed, whose requirements for pulse shape are significantly different. Optimization indexes are proposed for different loads to quantify the fitness of discharge pulse, transferring the pulse shaping problem into function optimization problem. For electromagnetic rail guns, the optimization index is the "acceleration ratio" of the projectile, which is the ratio of maximum acceleration and average acceleration during launch process. The larger acceleration ratio is, the flatter the waveform is. By expanding the concept of acceleration ratio, this index can be applied on flashlamps. For electro-thermal chemical guns, the concept of "shape variance" is proposed to measure the pulse shape. Simulation results show that the proposed optimization indexes are effective. With the help of intelligent optimization algorithm, we can get the optimized discharge pulse for different loads. Simultaneously, it is verified that the two-phase compulsator has strong flexibility in waveform adjustment.