Free latissimus dorsi muscle transfer is widely used for functional reconstruction of flexion of elbow and fingers after brachial plexus injury at later stage, as well as for soft tissue coverage because of its large size and long and reliable pedicle with adequate vessel diameter. Common complications recorded in literatures are hematoma and muscle atrophy due to a compartment syndrome. We treated a patient with soft tissue avulsion at forearm using free latissimus dorsi muscle transfer for soft tissue coverage in our hospital. Unfortunately during the transfer the patient's brachial plexus was injured. After timely treatment, he recovered completely.