Experimental studies were done to research the clinical effects of Yongdamsagantang and Yongdamsagantang-gamibang (Yongdamsagantang with Lonicerae Flos and Forsythiae Fructusadded) on the Anti-allergic effect in rats and mice. The results obtained as follows; 1. In the effects of Yongdamsagantang and Yongdamsagantang-gamibang on vascular permeability responses to intradermal histamine in rats, Yongdamsagantang group revealed none significant affect, but Yongdamsagantang-gamibang group revealed significant effect. 2. In the effects of Yongdamsagantang and Yongdamsagantang-gamibang on vascular permeability responses to intradermal serotonin in rats, Yongdamsagantang and Yongdamsagantang-gamibang group revealed significant effect. 3. In the 48hrs homologous passive cutaneous anaphylaxis in rats provoked by the IgE-like antibody against egg albumin, Yongdamsagantang group revealed none significant effect, but Yongdamsagantang-gamibang group revealed significant effect. 4. In the delayed type hypersensitivity responses to Picryl Chloride in mice, Yongdamsagantang and Yongdamsagantang-gamibang group revealed none significant effect, in the delayed type hypersensitivity responses to SRBC in mice, Yongdamsagantang group revealed none significant effect, but Yongdamsagantang-gamibang group revealed significant effect. According to above-stated results, Yongdamsagantang is none significant Anti-allergic effect. But Yongdamsagantang-gamibang is concluded to be effective as immediated type hypersensitivity and recommended to be used for the treatment of allergic diseases. (Asthma, Allergic urticaria, Allergic rhinitis, etc.)