Deformed vertebrae by cold shock in Rhynchocypris oxycephalus were discovered. Deformity was externally noticed in the caudal penducle region of R. oxycephalus. Radiographic and histologic investigation confirmed the deformity. Especially, histological investigations provided the fact that extensive fusion between neighbouring vertebrae is caused by removal of endogeneous mineralized tissue. Deformed vertebrae appeared suggesting the direct evidence of vertebral fusion had arisen internally by cold shock in this species.