Objective To investigate the clinical efficacy of Enzaishi intramuscular injection on patients with postherpetic neuralgia.Methods 120 patients with post-herpetic neuralgia who were hospitalized in Wuxi People's Hospital from January 2014 to December 2016,were randomly divided into the observation group (n =60) and control group (n =60).All patients were treated with oral vitamin B1 and mecobalamin,with an added gabapentin as control group,and adding-on oral gabapentin and intramuscular injection of grace as observation group.The clinical curative effect,pain degree and incidence of adverse reactions were compared between two groups.Results Total effective rate was higher in observation group[86.7 ％ (52/60)]than in control group[70.0％ (42/60)] (x2 =4.910,P =0.000).Post-therapeutic visual analog scale(VAS)pain score was lower in observation group than in control group(2.0 ± 1.1 vs.3.6± 1.7,P＜0.05),although the pre-therapeutic VAS pain score was similar between two groups(P＞0.05).Additionally,no serious adverse reactions were observed in the two groups,although the incidence of adverse reactions was higher in the observation group than in the control group(P＞0.05).Conclusions Enzaishi is safe and effective for the patients with senile neuralgia after herpes zoster,and could effectively reduce the pain degree.