Objective To investigate the clinical effect of vascularized and non-vascularized full-length phrenic nerve transfer on treating brachial plexus injury. Methods From August 1999 to March 2000, full-length phrenic nerve transfer to musculocutaneous nerve was conducted with the technique of Video-AssistedThoracic-Surgery in 15 patients(M 13, F 2)that all suffered from avulsion. Threekinds of procedures were carried out. The first was retaining initial point of phrenic nerve and dissecting full-length distal nerve (group A). The second waskeeping cervical segment and isolating thoracic segment of phrenic nerve (group B). The last was vascularized phrenic nerve transfer (group C). All these phrenic nerves were sutured to musculocutaneous nerves. The results of electrophysiology and function of biceps brachii muscle were compared. Results The lengthof the dissecting full-length distal nerves in group A, group B and group C compared with that of conventional operation increased by 17.8±1.1 cm, 10.2±1.0 cm and 8.8±0.5 cm respectively. There was significant difference when group A was compared with group B and group C, when group B was compared with group C. All three procedures had no significant difference and led to the same function recovery of biceps brachii muscle to grade Ⅲ about 6 months later. Conclusion There is no difference in treating effect between vascularized and non-vascularized full-length phrenic nerve transfer, when the recipientbed has normal vascularity.