The design of polymerase chain reaction (PCR) microchip system based on digital microfluidic technology is mainly to control the movement of micro droplets and the temperature of PCR reaction. In this paper, we designed a digital microfluidic PCR chip based on electrowettingondielectric(EWOD), and the temperature controlled to meet the requirements of PCR is designed and implemented in different regions on the chip. PCR microchip system based on digital microfluidic technology is composed of a dual substrate structure chip, a driving device for driving the chip and a temperature control module. The reaction region of the driving sample is realized to move to different temperature in the device, and the temperature required for the PCR reaction is satisfied in different reaction areas, and then realize the PCR.