Abstract: Objective To investigate the clinical characteristics and treatment of complex regional pain syndrome (CRPS). Methods Clinical data about 51 patients with complex regional pain syndrome admitted to our hospital from April 2000 to September 2016 were retrospectively analyzed. The patients were divided into different groups according to the disease course and gender, then the predisposing factors, concomitant disease, clinical manefestation and treatment for patients with CRPS were summarized. Results There were 22 cases (43.1%) with soft tissue injury history and 25 cases (49%) with sleep disorders. Pain was the chief complaint for all patients. Patients with short disease course (≤ 1 year) were prone to have limb dysfunction (χ²=4.404, P=0.036), patients with joint of lower extremity (χ²= 10.667, P=0.001) and multi-sited (χ²=32.980, P=0.000) involvement were more common seen. There were more female patients with osteoporosis than male patients (χ²=4.554, P=0.033), while male patients were prone to have limb swelling (χ²=5.368, P=0.026). CT was performed in 21 patients and 19 (91%) of them showed typical patchy osteoporosis and bone cyst degeneration. Patients who underwent bone scan (ECT) all showed lesion radioactivity, and 22 patients (43.1%) treated with bisphosphonates and 17 (33.3%) with hormone all achieved satisfactory pain relief. Conclusion CRPS is mainly caused by soft tissue injury, and middle- aged people are at high-risk. Joints of lower limbs are more likely to be involved. CT or ECT examination can guide clinical diagnosis, and steroids and bisphosphonates treatment are preferred therapies for patients with CRPS.