Artemisia princeps Pampanini, which is named as Sajabalssuk (SJ-1) in Korea, was fermented with lactic acid bacteria (LAB), and their antiallergic activities were investigated. When SJ-l was fermented with some LAB isolated from human feces, the inhibition of NO production in RAW264.7 cells and antioxidant activities of SJ-1 were not affected. However, the inhibitory activity of SJ-1 against degranulation of RBL-2H3 cells induced by IgE was increased by LAB fermentation. Among the LAB tested, Bifidobacterium infantis K-525 provided the most potent inhibitory effect of SJ-1 against degranulation of RBL-2H3 cells. SJ-1 extract fermented with B. infantis K-525 (F-SJ-1) potently inhibited the mouse passive cutaneous anaphylaxis reaction induced by IgE with antigen, skin dermatitis induced by 12-O-tetradecanoylphorbol-13-acetate, and scratching behaviors induced by compound 48/80. These inhibitory activities of F-SJ-1 were more potent than those of SJ-1. These findings suggest that the inhibition of SJ-1. extract against IgE-induced allergic diseases, such as rhinitis and asthma, can be enhanced by LAB fermentation.