To discuss clinical effect of Xiaoyou Decoction combined with Imiquimod on treatment of verruca plana and patients’ immune function.Methods:Fifty cases of verruca plana from February 2014 to October 2015 were randomly divided into observation group and control group.The observation group were given Xiaoyou Decoction combined with Imiquimod，and the control group oral acyclovir tablets combined with Imiquimod applied externally.The clinical curative effect，adverse reaction and sIL-2R and IL-2 levels in serum and recurrence were statistics that investigated in the research.Results:The clinical effectiveness of the observation group was significantly better than that of the control group(P<005).Adverse reactions of the 2 groups had significant difference(P>005).After the treatment，sIL-2 levels in serum of all patients increased notably，and that of the observation group was markedly lower(P<005)； level of IL-2R in serum of the 2 groups decreased dramatically(P<005)，and the observation group was greatly higher，comparatively(P<005)； the recurrence rate of control group was much higher than the observation group(P<005).Conclusion:By use of Xiaoyou Decoction combined with Imiquimod on treatment of verruca plana，the clinical curative effect was effectively improved，adverse reactions and the recurrence rate reduced，the patients’ immune function improved.It deserved popularization and application in clinical work.