The invention relates to a parking guidance system, which comprises a parking space monitoring sub-system and is characterized by further comprising a destination selection switch, a vehicle identification device, a vehicle detection sub-system, a guidance board sub-system and a central processor, wherein the destination selection switch and the vehicle identification device are arranged at the entrance of a parking lot; the vehicle detection sub-system is used for monitoring running tracks of vehicles in the parking lot, and the vehicle detection sub-system comprises a plurality of video processing modules which monitor preset sub-regions in the parking lot; and the central processor is in signal connection with the parking space monitoring sub-system, the vehicle detection sub-system, the guidance board sub-system, the destination selection switch and the vehicle identification device. The invention further discloses a parking guidance method based on the parking guidance system. According to the invention, guidance with a destination is provided for a driver, thereby providing more comfortable parking guidance experience for the driver. Meanwhile, the planned parking position is close to the destination of the driver, so that the driver is enabled to arrive at the destination more quickly, and the travel efficiency of the driver is improved.