Purpose: To assess the anti-obesity effect of liquid chromatography mass spectrometry (LCMS) profiled ethylacetate fraction (EF) of Anthocleista vogelii Planch on pancreatic lipase activity in vitro, and on obesity-related hormones in high-fat diet (HFD)-induced obese rats.Methods: Chromatographic analysis of EF to identify bioactive compounds was performed using LCMS electrospray ionization mass spectrometry (ESI-MS) positive mode. Thirty Sprague-Dawley rats were divided into 5 groups (n = 6). Group 1 was fed normal pellet diet, while groups 2 -5 were fed high-fat diet (HFD) for 14 weeks. The rats were treated for 4 weeks from week 10 with 125 mg/kg of EF (group 3), 250 mg/kg of EF (group 4) or 100 mg/kg of orlistat (group 5).Results: Seven alkaloids were identified in EF, namely, 10-hydroxycamtothecin, moschamindole, camptothecin, moschamine, N6-cis-p-coumaroylserotonin, sinomenine and desacetylcolchicine. The EF of A. vogelii exhibited inhibitory activity against pancreatic lipase with half-maximal inhibitory concentration (IC50) of 8.76 +/- 0.110 mu g/mL. Rats treated with EF (125 and 250 mg/kg) of A. vogelii showed significantly (p < 0.05) decreased feed intake, body weight, leptin and insulin, when compared to HFD controls. Cortisol, serotonin and noradrenaline were significantly (p < 0.05) increased, but changes in thyroid hormones levels in EF-treated rats were not significant (p > 0.05) when compared to HFD controls.Conclusion: The EF of A. vogelii demonstrate anti-obesity activities by inhibiting pancreatic lipase, elevating serotonin and noradrenaline, and increasing leptin sensitivity, leading consequently to decreased body weight of rats. However, the clinical use of EF of A. vogelii as an antiobesity herbal remedy requires further studies on its mechanisms of action.