Abstract: In this experiment, 44 rats were studied. The left sciatic nerve was transected. The proximal and distal stumps, tendon as well as vacancy were orderly introduced into the inlet and outlets of silastic Y-chamber or cross-chamber. 4 weeks later, the direction of nerve growth was observed. It was showed that proximal stump grew towards the distal stump rather than to the tendon and vacancy outlets. This indicats that there is of neurotropism or chemotaxis during rat peripheral nerve regeneration, which may be called tissue specificity. The chemotactic mechanisms, the distance between proximal and distal stumps and selective utilization of silastic material are discussed.