Objective: This study was designed to assess the efficacy and safety of neurotropin on the treatment of postherpetic neuralgia in patients with herpes zoster. Methods: 78 patients with postherpetic neuralgia were randomly divided into three groups: the control group A, the trial group B and C receiving neurotropin by intravenous infusion at dosage of 3.6 or 10.8 u once daily respectively. Results: During the treatment, the degree of pain relieved in the trial groups was more markedly than that in the controls. Conclusion: The results suggest that neurotropin is an effective and safe agent for treatment of postherpetic neuralgia.