The invention discloses a transmission device of a positive and negative polarity conversion DC voltage generator. The transmission device is provided with the DC voltage generator, wherein a transmission structure is arranged inside the DC voltage generator, the transmission structure is composed of insulated lead screws and a motor, the motor drives the insulated lead screws to move, silicon stacks are arranged inside the DC voltage generator, each silicon stack is provided with a fixing nut, and the motor drives the fixing nuts to move. According to the transmission device, the insulated lead screws are arranged in the DC voltage generator, through the cooperated motion of the insulated lead screw and the motor, positive and negative polarities of the silicon stacks can be converted quickly, the positive and negative polarity conversion is convenient, the traditional method of adopting a gear for transmission is avoided since the insulated lead screw and the motor are adopted, an oil path does not need to be arranged, and the phenomenon of oil leakage in the silicon stacks is avoided, so that the transmission device is more stable in operation and good in contact.