Inflammatory cells play a critical role during nerve regeneration following peripheral nerve injury. In this study, we investigated immune responses in rat sciatic nerve after injury. Wistar rats were randomly divided into the sciatic nerve injury (model) group and control group. The right sciatic nerve of rats in the model group was transected and sutured end-to-end. Our results showed that rats in the model group functionally recovered following sciatic nerve injury. We detected inflammatory cell infiltration in the remaining sciatic nerves following injury. In addition, expression of interferon-γ (INF-γ), interleukin-10 (IL-10), and the INF-γ/IL-10 ratio was significantly elevated one week following nerve injury, but gradually decreased thereafter. Our findings demonstrate that immune responses and inflammatory cell activation are involved during recovery from sciatic nerve injury.