Gravel grading filter

The utility model relates to the field of filters, in particular to a gravel grading filter which comprises a base, the top end of the base is fixedly connected with a supporting body and a supporting assembly, the top end of the supporting body is hinged to a box body, a motor is installed on the supporting body, the driving end of the motor is fixedly connected with a first screw rod, and the first screw rod is in threaded connection with the inner side of a movable block. The moving block is rotationally connected with one end of a supporting rotating plate, and the other end of the supporting rotating plate is rotationally connected with a protruding block at the bottom of the box body. When gravel on the filter screens needs to be cleaned, a motor is started to drive a first screw rod to rotate, a movable block moves towards the direction of the motor to drive a supporting rotating plate to move, the box body is made to incline, and therefore the three filter screens are made to incline, meanwhile, a vib