The invention discloses an automatic mold cleaning device for a PC component production line. The device is composed of a cleaning pool, a lifting table, a moving device, a slag-water separating device, a clamping device and a cleaning manipulator, the moving device is composed of a transverse moving trolley, a longitudinal moving trolley and a longitudinal moving cart, the slag-water separating device is composed of rotating wheels and a high-frequency vibrating screen, and the clamping device is composed of a clamp, a connecting rod device, a first hydraulic device, a large bevel gear, a small bevel gear and a second hydraulic device. The cleaning manipulator is composed of a movable base, a hydraulic supporting base, a mechanical arm, a high-pressure spray head and an electric steel wire rolling brush. Particularly, the device is a device with automatic clamping and cleaning functions for quickly cleaning a side mold, and belongs to the field of PC component production equipment. The automatic mold cleaning device has the beneficial effects that the cleaning efficiency is improved, the service life of the mold is prolonged, the water circulation utilization rate is increased, resources are saved, and the cost is reduced by combining a physical cleaning method and clean water cleaning.