The utility model relates to a chain tensioning clamp for an all-purpose testing machine. The chain tensioning clamp for the all-purpose testing machine comprises an upper clamp body and a lower clamp body. The upper clamp body and the lower clamp body are provided with a reversely herringbone groove and a herringbone groove respectively. Chain stop blocks are respectively installed in the reversely herringbone groove and the herringbone groove respectively. The smallest distance between the chain stop blocks of the upper clamp body and the smallest distance between the chain stop blocks of the lower clamp body are respectively smaller than the width of a chain clamped by the chain tensioning clamp. Compared with the prior art that a planar chuck is directly used for clamping the chain, the chain tensioning clamp for the all-purpose testing machine is not prone to slippage in the clamping process, the clamping force can be adjusted automatically along with change of testing force, clamping is stable and reliable, and the accuracy of a tensioning test is improved.