The utility model relates to an underwater robot for collecting suspended solid, including main frame cavity, the string bag, buoyancy module, underwater lighting lamp, driving system, the control unit, driving system including the symmetry set up a pair of tubular screw propulsion ware of the inside left and right sides of main frame cavity, and the symmetry set up the vertical integrated motor propeller in the outside left and right sides of main frame cavity, the absorption power supply of suspended solid under propulsion source that tubular screw propulsion ware goes on forward as the underwater robot simultaneously and the adsorbed water, the string bag can be dismantled with the main frame cavity and be connected, connects the position and is equipped with force sensor, and the control unit is connected with force sensor, driving system electricity respectively. The utility model discloses tubular screw propulsion ware sets up in the main frame cavity, and ahead running functionexcept general has production pressure differential concurrently, draws the function of target object, and complicated actuating mechanism of economization and motion control's complexity controls simply, easy and simple to handle.