The invention provides a flat panel detector system and a rapid awakening method thereof. The flat panel detector system comprises, at least, an X-ray sensor, a standby voltage stabilizing circuit, an acquisition circuit, a main CPU control processing unit, an image display unit, a battery unit, a low-noise voltage stabilizing circuit, a switching power supply and an auxiliary CPU power supply management unit. The auxiliary CPU power supply management unit is used for providing standby and awakening time sequence control of a flat panel detector and meanwhile conducts powering-on and powering-off control on the battery unit, the low-noise voltage stabilizing circuit and the switching power supply respectively. Standby and awakening time sequence control is conducted on the flat panel detector by adding the auxiliary CPU power supply management unit, and when the flat panel detector is standby, powering on for the X-ray sensor is kept, and meanwhile part of circuit constitution unit is closed to reduce the standby power consumption of the flat panel detector. In addition, the flat panel detector can be rapidly awakened, and improvement of clinical experience of a user is promoted.