Complex regional pain syndrome (CRPS) is a disease characterized especially by pain, swelling, limited range of motion (ROM), vasomotor instability, and atrophy of bones in the extremities. In rehabilitation, it is important to suppress excessive sympathetic activity and break the vicious cycle of pain. This is achieved with mild ROM exercise and a mental approach. In this case, the patient had severe pain, swelling, redness, and excessive sweating of the right hand. With alternating warm and cold bath therapy, his symptoms were gradually alleviated. Alternating warm and cold bath therapy may help in the treatment of CRPS.