This study evaluated the anti-obesity effect of soluble and insoluble oat dietary fiber on high-fat diet-induced obese mice. 60 mice were first fed with high-fat diet to establish obesity model. Then, obese mice were fed with high-fat diet that contains different doses(7.33 and 14.67 g kg-1 BW d-1) of oat soluble (SDF) and insoluble (IDF) dietary fiber. Other mice fed with normal diet and high-fat diet were used as normal control (NC) group and obesity model group, respectively. Variation of related indexes was measured.It suggested that both SDF and IDF oat dietary fibers significantly decreased the Lee's Index (P<0.05), especially for IDF. Besides, they could promote the fat breakdown (P<0.05) and improve the activity of hormone sensitive lipase (P<0.05). The fasting serum insulin level declined significantly (P<0.05) compared with model group, meanwhile, and the thyroid stimulating hormone level significantly increased (P<0.05), and SDF were more effective (P<0.05). In addition, the hepatic Index and the hepatic lipid levels including TC and TG were decreased (P<0.05), while the activity of hepatic lipase (HL) and LPL were (P<0.05) increased. However, compared with normal control group, significant difference was indicated (P<0.05), and SDF was more effective. The present results showed that oat SDF and IDF were beneficial to anti-obesity with dose effects, but function channel was varied. ©, 2015, Editorial Department, Chinese Cereals and Oils Association. All right reserved.