Abstract: The causes of prepulse origin in pulse power machine especially in Blumlein pulser are analyzed in this paper. A method that can reduce the prepulse by an inductance between Marx and zero voltage node has been presented while a calculation example used Pspice is provided. The prepulse switches can been used to reduce the prepulse effects in many fields. The prepulse requests for wire arrays in Zpinch experiments are analyzed and explained by means of specific reaction quantity and vaporization heat, the results of the calculations are similar. In fact, the results of experiments indicate that the energy deposited in the wires is sufficient to bring the aluminicom wires to partial or total vaporization. Because the value of prepulse current is larger than that of calculation, this indicat