The brachial plexus injury causes a catastrophic loss of functions of the corresponding upper extremity. However, for a long time, it must have been treated by conservative methods. Recently, with the development of the microsurgery, the brachial plexus lesions were begun to be treated by surgical means, such as neuroiysis, interfascicuiar nerve graft, or neurotization. We experienced seven cases, managed by interfaseicular nerve graft under the operating microscope, and here we presented four cases with the over-one-year results after operations.