Alcohol metabolizing activity of fermented sea tangle juice (FSYJ) using Lactobacillilus brevis BJ20 were evaluated by measuring relative alcohol dehydrogenease (ADH) and aldehyde dehydrogenase (ALDH) activities. According to the results of MTI assay. the fermented sea tangle juice by Lactobacillilus brevis BJ20 appeared safe in the cytotocxity. The relative ADH activity of FSTJ showed 124% at 10 mg/mL, which increased with increasing concentration. The relative ALDH activity showed, however, insignificant difference (P>0.05) between concentrations of FSTJ up to 50 mg/mL. These results suggested that fermented sea tangle juice by L. brevis BJ20 could be used as a potential material for metabolizing alcohol.