Objective:To investigate the clinical curative effect of hyperbaric oxygen (HBO) on postherpetic neuralgia (PHN).Methods:A total of 80 patients, who were treated in Dermatology Department of Naval Anqing Hospital from the August of 2016 to the August of 2018 and met the inclusion criteria, were enrolled and randomly divided into control group and study group according to the random number table method, with 40 cases per group. The patients in the control group were treated with modified Tuolixiaodu powder. The patients in the study group were treated with HBO combined with modified Tuolixiaodu powder. The efficacy, visual analogue scale (VAS) score, quality of life score and brain-derived neurotrophic factor (BDNF) expression of the two groups were observed.Results:The effective rate of the study group was 95.0% (38/40), and that of the control group was 70.0% (28/40). The difference between the two groups was statistically significant ( P=0.019). The efficacy of the study group was obviously better, and the difference between the two groups was statistically significant ( P=0.032). Compared with those before treatment, the VAS scores of both groups after treatment decreased, with statistically significant difference ( P<0.05). Compared with those before treatment, the scores of the life quality of both groups obviously increased, with statistically significant difference ( P<0.05). The patients of the study group gained better curative effects, e. g. at their work, study, and daily life, and the two groups had significant differences ( P<0.05). The BDNF expression levels in the study group and the control group both increased after treatment, with statistically significant difference ( P<0.05). Conclusion:The combination of HBO to the treatment of modified Tuolixiaodu powder on PHN can improve its action of replenishing qi and blood, promoting blood circulation, and relieving pain by dispersing stasis, to improve patients' life quality and the expression level of BDNF.