In this paper, newly designed plastic Cu 51 Zr 37 Ti 8 Ni 4 bulk metallic glass has been successfully fabricated. By purposely increasing the liquidus temperature in a quaternary Cu–Zr–Ti–Ni alloy system, glass-forming ability of as-cast bulk metallic glasses shows a desired decrease trend. As-cast Cu 51 Zr 37 Ti 8 Ni 4 , which has a lower glass-forming ability and a higher liquidus temperature than Cu 52 Zr 37 Ti 8 Ni 3 , is of monolithic amorphous structure, and also displays remarkable plasticity of 10.5% together with the fracture strength of 2145MPa. Multiple and interactive shear bands can be discovered on the fracture surface of fractured Cu 51 Zr 37 Ti 8 Ni 4 . In addition, the deformation of Cu 51 Zr 37 Ti 8 Ni 4 shows serrated flow behavior. By a statistics analysis of serrations in the stress–time curve, the serrated flow behavior of the sample follows the self-organized critical behavior. This work suggests that, with the aid of CALPHAD, composition design of plastic bulk metallic glasses can be achieved according to the liquidus perspective.