These studies were conducted to investigate the effects of the extracts from Hoelen alba, Alismatis Rhizoma and Atractylodes Rhizoma on the proliferation and differentiation of 3T3-L1 cells. The results were summerized as follows: Hoelen alba and Alismatis Rhizoma extracts inhibited the proliferation of preadipose 3T3-L1 cells. In inductive differentiation, all three extracts inhibited the adipose conversion in 2 days of initial-culture, Atractylodes Rhizoma extract inhibited the adipose conversion in 5 days of final-culture and Hoelen alba and Alismatis Rhizoma inhibited adipose conversion in treatment of whole term of culture. In spontaneous differentiation, Atractylodes Rhizoma extract increased the adipose conversion in 2 days of initial-culture, Hoelen alba and Alismatis Rhizoma increased the adipose conversion in 5 days of final-culture, all three extracts increased adipose conversion in treatment of whole term of culture. The 10% serum of mice treated with each sample did not affect, but the 5% serum of them inhibited the proliferation of 3T3-L1 cells. In inductive differentiation, the 10% serum of them inhibited the adipose conversion in treatment of whole term of culture.