Objective: To evaluate the effect of 'Inducing and Expelling’principle in traditional Chinese medicine for the treatment of psoriasis. Method: One hundred cases of psoriasis treated by Yinxiaoping granule(4.5

9.0 g·d-1)were included in the retrospective analysis. The treatment duration depended on the conditions of the patients. Statistical analysis was carried out for the analysis based on patient’s condition

the degree of the suffering and the recurrence. Result: The analysis indicates that the longer the suffering duration was

more serious the patient’s condition

and more frequent the recurrence (P<0.05 or P<0.01). In the case of a long treatment of western medicine has been taken

the treatment of Yinxiaoping granule was extended accordingly. The inducing duration

the extinctive duration and the recovery duration were also extended respectively(P<0.05 or P<0.01). There was no need to be dietetic restraint for the treatment of 'Inducing and Expelling’. Some of the inducing food even could be helpful for the efficacy. Yinxiaoping granule decreased and delayed the recurrence. Conclusion: Yinxiaoping granule decreases and delays the recurrence of psoriasis. The treatment of 'Inducing and Expelling’opens a new concept and approach for the treatment of psoriasis.