Abstract： Objective To explore the therapeutic effect and pain stress response of ultrasound-assisted intercostal nerve block in the treatment of postherpetic neuralgia(PHN).Methods Altogether 88 patients with postherpetic neuralgia admitted to our hospital from October 2021 to December 2023 were selected and randomly divided into the control group(n=44)and the observation group(n=44)according to random number table method.The control group received blind intercostal nerve block treatment,while the observation group received ultrasound assisted intercostal nerve block treatment.The total clinical effective rate of the two groups of patients after 8 weeks of treatment was recorded.The Visual Analog Scale(VAS)was used to record the pain levels of two groups of patients before treatment and after 1,2,4,and 8 weeks of treatment.The serum immunoglobulin levels of two groups of patients before treatment and after 8 weeks of treatment,including immunoglobulin G(IgG),immunoglobulin M(IgM),and serum high mobility boxl(HMGB1)and CXC chemokine ligand 10(CXCL-10)were recorded.Meanwhile the quality of life levels of two groups of patients after 8 weeks of treatment were recorded using a quality of life scale.Results After 8 weeks of treatment,the total effective rate of the observation group(93.2％)was higher than that of the control group(77.3％),and the difference was statistically significant(P＜0.05).The VAS scores of the observation group were lower than those of the control group after 1 week,2 weeks,4 weeks,and 8 weeks of treatment,and the difference was statistically significant(P＜0.05).After 8 weeks of treatment,the level of IgG in the observation group was higher than that in the control group,while the levels of HMGB1 and CXCL-10 in the study group were lower than those in the control group,with statistical significance(P＜0.05);the quality of life score of the observation group was higher than that of the control group,and the difference was statistically significant(P＜0.05).Conclusion Ultrasound assisted intercostal nerve block therapy can effectively alleviate neuropathic pain in patients with PHN,increase serum immunoglobulin levels,reduce serum HMGB1 and CXCL-10 levels,and improve the prognosis of patients.