Objective To investigate the therapeutic effect of Xiaoxuan Kangfu capsule in treating psoriasis vulgaris. Methods All patients were divided into two groups randomly (60 patients in a control group and 60 patients in a treatment group). In the control group complex Qingdai capsule was given to the patients, with 4 pills for each time and 3 times daily. While in treatment group Xiaoxuan Kangfu capsule was given to the patients with 6 pills for each time and twice daily. 30 days consisted one treatment period for both groups. The patients undertook one to three treatment period according to the patients' pathogenetic condition. The rates of recovery and improvement and were compared. Results In the treatment group, 34 patients were cured (42.5%), and the total effective rate was 87.5%; while in the control group 14 patients were cured (7.5%), and the total effective rate was 72.5%. There was statistic difference between the two groups (P＜0.05). The average heal time of the treatment group was shorter than that of the control group, showing statistic difference (P＜0.05).Conclusion Xiaoxuan Kangfu capsule showed higher recovery rate, shorter healing time and lower recurrence rate in treating psoriasis vulgaris than complex Qingdai capsule. The treatment is deserving clinical spread.