This research aimed to formulate quercetin (Qu) and curcumin (CUR)-loaded PLGA NPs coated with chitosan (CS) & PEG and to explore their therapeutic effect against obesity in rats. Qu and CUR nanostructures were prepared and characterized by Zetasizer and TEM. Then, the formulated nanoparticles and their free couterparts were employed for mitigation of obesity in female rats. The size of NPs was in nanometer range with an average size distribution 307.9 nm for Qu NPs and 322.5 nm for CUR NPs. The Qu NPs and CUR NPs were appeared in the TEM image containing core in which the Qu or CUR was localized and surrounded by the coat of PLGA-CS-PEG. The Qu NPs exhibited negative zeta potential at -8.5 mV, while, CUR NPs exhibited positive zeta potential at +0.916 mV. Treatment with orlistat, free Qu, Qu NPs, free CURor CUR NPs elicited significant decline in body weight, BMI and Lee index. Orlistat and CUR NPs significantly diminished liver, heart and visceral adipose tissue weights. Furthermore, the suggested treatments significantly reduced the gonadal and subcutaneous adipose tissue weights. Orlistat significantly lessened kidney and adrenal weights. All treatments significantly minimized serum Chol., TG, LDL, glucose, INS, HOMA-IR, LH, MDA, TLR4 and NF-κB levels and elevated serum HDL, E2 and TAC levels. Orlistat significantly enhanced serum IL-10 level. Conclusively, Qu and CUR nanoformulations offer anti-obesity potency through their hypolipidemic, hypoglycemic,antioxidative and anti-inflammatory effects. Both Qu and CUR NPs manifested superior effect than their free counterparts, may be because of solubility elevation as well as bioavailability of the nanoencapsulation.