The invention provides test-piece clamping pincers for CTOD testing. The test-piece clamping pincers comprise a supporting frame, two sets of main pincers and two sets of auxiliary pincers. The supporting frame is an H-shaped member, and connecting rods arranged oppositely are arranged on the two sides of the supporting frame. The two connecting rods are connected through a middle rod. The connecting rods are arranged in parallel. Each set of main pincers is composed of two main pincers assemblies. Each set of auxiliary pincers is composed of two auxiliary pincers assemblies. Each main pincers assembly comprises a pincers handle, an adjusting rod, a large crutch, a pincers foot and a first pressing spring, all of which are connected in sequence. Each auxiliary pincers assembly is composed of a pincers crutch, a lengthening rod, a small crutch, a pincers claw and a second pressing spring, all of which are connected in sequence. Accordingly, the test-piece clamping pincers are safe, reliable and easy to use, the situation that when a medium or large test-piece is tested, due to falling of the test-piece, accidents are caused, or cooling liquid splashes, and operators are injured can be effectively avoided, and the safety of testing is improved.