Objective To explore the efficacy and safety of 5-aminolevulinic acid photodynamic therapy for moderate to severe facial acne.Methods A total of 94 cases of moderately severe acne were selected from October 2015 to June 2017,and were divided into control group(n=47)and observation group(n=47).The patients in control group were treated with red and blue light,while the patients in observation group were treated with 5-aminolevulinic acid photodynamic therapy.Clinical curative effect,serum TNF-αand IL-8 levels and adverse reactions of the two groups were compared.Results After treatment for 2,4 and 8 weeks,the effective rates of the observation group were significantly higher than those of the control group,and the difference was statistically significant(P<0.05).Serum TNF-αand IL-8 level of observation group after treatment was lower than that of the control group(P<0.05).The incidence of adverse reactions was 12.77%in the observation group and 8.51%in the control group.There was no significant difference between the two groups(P>0.05).Conclusion The efficacy of ALA-PDT in the treatment of moderate to severe acne was significantly better than red and blue light treatment,and the recurrence rate was low,it is worthy of clinical application.