The present invention provides a method for reducing the expressions of the sterol regulatory element-binding protein 1C (SREBP-1C), acetyl-CoA carboxylase (ACC), and stearoyl-CoA desaturase 1 (SCD-1), comprising administering to a subject a composition comprising an effective amount of a longan pericarp extract. The longan pericarp extract significantly inhibits lipogenesis, reduces the glutamic-pyruvic transaminase (GPT) index, and protects the liver.