The invention relates to liquid waste treatment tank comprehensive cleaning equipment. The liquid waste treatment tank comprehensive cleaning equipment comprises a top supporting plate, supporting devices, a cleaning device and a suction device. The front and rear ends of the supporting plate are each provided with an expansion groove. One supporting device is mounted in each expansion groove of the supporting plate. The cleaning device is mounted on the lower end face of the middle portion of the top supporting plate. The suction device is mounted on the cleaning device. The suction device comprises a scraping plate electric sliding block, a scraping connecting plate, a scraping angle plate, a scraping angle push rod, scraping cylinders, scraping sliding columns, a sliding column connecting plate, a scraping mechanism, a suction mechanism and sliding column springs. Through the liquid waste treatment tank comprehensive cleaning equipment, the problems that an existing liquid waste treatment tank is large in cleaning difficulty, low in cleaning efficiency and not thorough in cleaning, the sidewall of the treatment tank cannot omnidirectionally at a time, sundries cleared off from the treatment tank cannot be automatically gathered and the cleaning difficulty of the sundries at the bottom of the treatment tank is large can be solved.