Objective Research in the therapeutic effect and mechanism of micro - circulation barriers after Fractured Limb (fingers) Replantation (FLR) applied with Hyperbaric Oxygen. Method The research objectives are 33 paints who are suffering from micro- circulation barriers after FLR, and the ordinary clinic therapy is unsatisfactory. After 10 to 20 times of Hyperbaric Oxygen treatment, the statistic is worked out according to clinic therapeutic effect standard. Thus, the effective rate reaches 86.11%. The comparison of therapeutic effects before and after the treatment is obviously different (P < 0.01 ). Conclusion The therapeutic effect is absolutely gorgeous if applied Hyperbaric Oxygen to subside rnicrocirculation barriers after FLR. The therapeutic. Mechanism is to sooth anoxic state, improve microcirculation, and facilitate the retrieval of fractured limb (fingers).