Black ginseng is produced by a repeated steaming process. The aim of this study was to investigate the anti-obesity effects of black ginseng ethanol extract (BG-EE) in high fat (HF) diet-fed mice. Two groups were fed either a normal control (NC) diet or a HF diet (45% kcal fat). The other three groups were given a HF diet supplemented with 1% BG-EE, 3% BG-EE, and 5% BG-EE for 12 wk. The anti-obesity effects of the BG-EE supplement on body weight, the development of fat mass, and lipid mechanisms were assessed in obese mice. HF-induced hyperlipidemia, fat accumulation in the liver, and white adipose tissues were reduced after BG-EE supplementation. Total fecal weight and the amount of fecal fat excretion also were increased after BG-EE supplementation. These results suggest that BG-EE may be useful to ameliorate HF-induced obesity through the strong inhibition of fat digestion.