Abstract： Objective： To observe the clinical effect of Yinxian Zhiyang Decoction on subacute eczema and its mechanism. Methods：A total of 66 patients with subacute eczema of damp-heat immersion type who were diagnosed at the Department of Dermatology， Zhejiang Provincial Hospital of Traditional Chinese Medicine from June 1， 2023 to June 1，2024 were selected. They were divided into the treatment group and the control group according to the random number table method，with 33 cases in each group. The control group was treated with oral administration of Loratadine Tablets，and the treatement group was treated with Yinxian Zhiyang Decoction. Both groups were treated for four weeks. The clinical effects and incidence of adverse reactions， and the changes in the scores of Eczema Area and Severity Index （EASI）， pruritus scores， skin flora culture and levels of serum interleukin-17 （IL-17） before and after treatment were compared between the two groups. Results：After two and four weeks of treatment，the EASI scores in the two groups were decreased when compared with those before treatment， differences being significant （P＜0.05）. After four weeks of treatment， the EASI score in the treatment group was lower than that of the control group， the difference being significant（ P＜0.05）. After two and four weeks of treatment，the pruritus scores in the two groups were reduced when compared with those before treatment （P＜0.05），and the pruritus score in the treatment group was lower than that in the control group at the same time point （P＜0.05）. After four weeks of treatment， the detection rate of Staphylococcus aureus，Staphylococcus epidermidis and Malassezia in the two groups dwindled when compared with those before treatment （P＜0.05）， and the detection rate of Staphylococcus aureus， Staphylococcus epidermidis and Malassezia in the treatment group was lower than that in the control group （P＜0.05）. After treatment， the levels of serum IL-17 in the two groups were down-regulated when compared with those before treatment （P＜0.05），and the IL-17 level in the treatment group was lower than that in the control group （P＜0.05）. There were no obvious adverse reactions in the two groups. Conclusion：The oral administration of Yinxian Zhiyang Decoction can effectively inhibit the body's inflammatory responses of patients with subacute eczema， relieve the clinical symptoms， and regulate the distribution of skin flora.