The invention relates to a feeding clamping adjusting device. The feeding clamping adjusting device comprises a base, a supporting base and a lifting mechanism. The lifting mechanism comprises a box body, a supporting frame and a conveying mechanism, wherein the supporting frame and the conveying mechanism are arranged in the box body. The supporting base is fixed to the top face of the box body and driven by the lifting mechanism to ascend and descend. The supporting frame comprises two supporting legs movably installed in a shear shape. One end of each of the two supporting legs is movably installed on the top face; the other end of the first supporting leg is movably installed on the bottom face of the box body; and the other end of the second supporting leg is arranged on a conveying belt of the conveying mechanism and is held by a limiting block fixed to the conveying belt. The conveying belt is controlled by a motor of the conveying mechanism to move. The supporting base comprises a clamping plate, a supporting beam used for supporting a plurality of to-be-positioned workpieces, and two limiting columns fixed to the two opposite ends of the supporting beam. The clamping plate is locked on the supporting beam through a plurality of bolts of operating parts with the tops in a butterfly shape, and the multiple to-be-positioned workpieces are clamped on the supporting beam.