The invention relates to a full-automatic cleaning device for car parts. The full-automatic cleaning device comprises a left electric lifting door, a row of nozzles, a lifting table, a feeding trolley, a heater, a temperature sensor, an ultrasonic generator, an oscillator, a filter device, a first water pump, a pipeline, an electric control cabinet, a dryer, a lifting rod, a second water pump, a right electric lifting door, a high-temperature water tank, a cleaning tank, a travelling table, a cleaning box and a hot water pump. By adopting water as the cleaning medium, the full-automatic cleaning device is safe, cheap, simple and practical and does not harm the human body, and cleaning water can be recycled so that resources can be saved. High-pressure spray washing and ultrasonic oscillating are adopted, work-pieces are gradually cleaned from rough cleaning to intensive washing, and therefore the parts can be cleaned completely and totally. An electric control system is adopted for achieving stable and reliable full-automatic operation from feeding to discharging, and therefore the cleaning quality of products can be stable.