A multifunctional rod clamp is an operation tool in industry, overcomes the defects in the prior art, and has the follow structure relationship: non-tooth jaw is arranged at one end of a clamp handle; a spring is installed at the outer side of the non-tooth jaw, a lock stem penetrates through and is inserted in the spring, and a spring catch is arranged in front of the spring; a pressing cap is fixed at the outer side of the non-tooth jaw; and a clamping piece is connected in a intermediate tank of the clamp handle by a rotating bolt and latch bolts, and one side of the clamping piece is positioned at the inner side of the non-tooth jaw. The rotating bolt is arranged in the middle of the clamping piece, and the latch bolts are arranged at the periphery of the rotating bolt; the clamping piece is arranged at the inner side of the non-tooth jaw, and the rotating bolt is arranged in the middle of the clamping piece, and the latch bolts are arranged at the periphery of the rotating bolt; when the rod clamp is used, the torque is increased by the conical degree of the jaw, so that the rod clamp can adapt to different pipe diameters automatically, and adapt to the plastic deformation caused by applying stress on the pipe through the jaw automatically; and under the effect of reducing the pipe diameter, the rod clamp can ensure the torque, and can not slip, thus conducting disassembly and fastening.