The invention discloses an automatic maintenance control system for tube well dewatering and relates to the field of geotechnical engineering. The utility model relates to a device capable of automatically controlling the dewatering depth in the deep foundation pit dewatering design and construction process. A special switch is manufactured and connected with two floaters, and a power switch is flexibly controlled by means of gravity and buoyancy of the floaters. Meanwhile, the distance between the two floaters is the required water level reduction depth in the tube well, whether a switch is turned on or off can be automatically determined according to the actual reduction depth and the water level in the tube well, and real-time control is achieved; Moreover, the water level height of theprotection motor can be determined by adjusting the distance between the floater and the submersible pump motor according to needs, and motor burnout is avoided.