We studied the effect of epigallocatechin-3-gallate(EGCG) on the adipose conversion of 3T3-L1 cells by insulin. In the 10 days of culture with insulin, the fat cells exhibited the increased and larger intracytoplasmic lipid droplets. In contrast, the levels of triglyceride(TG), a marker of adipose conversion, were decreased. However, the levels of glucose were decreased in the adipose conversion. In addition, levels of cholesterol were decreased in the differentiated 3T3-L1 cells.