AIM: To study the effect of Qingdaipowder Gel (QDPG) on mice specific dermatitis (AD) model and the antibacterial effect of the ethanol extract of Qingdaipowder.  METHODS: AD model of mice was established by repeated skin induction with 2,4-dinitrochlorobenzene (DNCB). Fifty-six mice were randomly divided into blank group, model group, Hydrocortisone Butyrate Cream group (Hyd, 1.5 mg/cm2), matrix group, high dose group of Qingdaipowder Gel (QDPG-H, 240 mg/cm2), medium dose group of Qingdaipowder Gel (QDPG-M, 120 mg/cm2), and low dose group of Qingdaipowder Gel (QDPG-L, 60 mg/cm2). For external use, the drug was administered to the skin once a day for 12 consecutive days. The skin lesions, auricle swelling, thymus and spleen index of mice in each group were analyzed. Hematoxylin eosin (HE) staining was used to observe the pathological changes of skin lesions, and enzyme-linked immunosorbent assay (ELISA) was used to detect serum immunoglobulin E (IgE), interleukin-6 (IL-6), interleukin-4 (IL-4), and tumor necrosis factor α (TNF-α) and γ Interferon (IFN-γ) Level of inflammatory factors. Filter paper method and minimum inhibitory concentration (MIC) method were used to determine the antibacterial activity of the ethanol extract of Qingdaipowder against Staphylococcus aureus and Escherichia coli, the main pathogens of specific dermatitis. RESULTS: Compared with the model group, the degree of auricle swelling and the thickness of cortex in Hyd group and QDPG groups decreased significantly (P<0.01), and the serum levels of IL-4, IL-6, IgE, IFN-γ And TNF-α The level decreased significantly (P<0.01), IFN- γ/The ratio of IL-4 increased (P<0.05), and the thymus spleen index decreased (P<0.05) in QDPG-H group. The MIC values of the ethanol extract of Qingdaipowder against Escherichia coli and Staphylococcus aureus were 31.25 mg/mL and 62.5 mg/mL, respectively. CONCLUSION: QDPG can effectively alleviate the symptoms of specific dermatitis, and its mechanism of action can improve the skin lesions of AD model mice by inhibiting pathogenic bacteria and regulating the balance of T helper cells TH1/TH2.