The invention discloses a clamping device. The clamping device comprises a clamping body and a fixing base, wherein a mounting hole is formed in the clamping body; a mounting screw is arranged in the mounting hole; the clamping body is fixed on the fixing base through the mounting screw; each of the top edge and the bottom edge of the fixing base is provided with an arc insertion block; a fixed hole is formed in the center of the fixing base; a fixing screw is arranged in the fixed hole; the fixing base enables the arc insertion blocks to insert into the wall under the effect of the fixing screw; a clamping cavity is arranged at the front of the fixing base; the clamping body includes a semicircular clamping block and a clamping compressed tablet which is fixed on the semicircular clamping block; the diameter of the semicircular clamping block is greater than the length of the clamping cavity; and the clamping body is movably clamped in the clamping cavity through the semicircular clamping block so as to be fixed on the fixing base. The clamping device is simple in structure and convenient in operation, can effectively reduce the mounting loss, and is high in usage stability, applicability and practicality.