The aim of this study was to evaluate eight plants extract for porcine pancreatic lipase inhibition, characterizing biochemically the extract with high inhibitory activity and its effects on preventing weight gain in female rat fed a high-fat diet (HFD). In vitro pancreatic lipase inhibition was carried out in ρ-nitrophenyl-laurate substrates and a double-reciprocal plot was used for inhibition mechanism identification. In vivo experiments, female rats were fed with a standard diet or high fat diet (HFD), HFD+orlistat, HFD+22.5 mg/ml GT, and HFD+112.5 mg/ml GT. Feed intake, weight body gain, fecal lipid excretion and biochemistry parameters were analyzed. Camellia sinensis extract had the highest inhibitory lipase activity (76.65 ± 2.04%) with a non-competitive inhibition. C. sinensis administration, equivalent to 112.5 mg/ml, promoted weight loss, while 22.5 mg/ml increased fecal excretion of lipids in 31.41%. C. sinensis extract is certainly a promising alternative for preventive obesity treatment, since biochemical parameters analyzed showed significantly, reduction in the serum triglycerides levels and significantly decreased the LDL-cholesterol basal levels when compared with animals that did not receive a fat diet.