To investigate the mechanism, diagnosis, and treatment of common fibular nerve compression syndrome secondary to sciatic nerve injury.Based on the clinical manifestation and Tinel's sign at fibular tunnel, 5 cases of common fibular nerve secondary compression following sciatic nerve injury were identified and treated by decompression and release of fibular tunnel. All 5 cases were followed up for 13-37 months, 25 months in average, and were evaluated in dorsal flexion strength of ankle.The dorsal flexion strength of ankle in 4 cases increased from 0-I degrees to III-V degrees, and did not recover in 1 case.Fibular tunnel is commonly liable to fibular nerve compression after sciatic nerve injury. Once the diagnosis is established, either immediate decompression and release of the entrapped nerve should be done or simultaneous release of fibular tunnel is recommended when the sciatic nerve is repaired.