Abstract: Understanding how food ingredients interact between themselves contributes to scientific advancement in food science and to the development of products with optimized sensory, functional, and technological properties. In addition to relevant nutritional characteristics, β-lactoglobulin (βLG) can bind to hydrophobic bioactive compounds such as resveratrol (RES) and thus improve its antioxidant capacity and solubility. This work aimed to determine the thermodynamics of βLG-RES nanocomplexes formation. Analyzes were performed by fluorescence spectroscopy, at pH 7.4, temperature ranged from 25 to 40 °C, fixed βLG concentration (1.5 x 10-6 mol. L-1) and variable RES (1.78 x 10-6 to 1.93 x 10-5 mol.L-1). Complex formation stoichiometry indicated that two βLG binding sites are required for a RES molecule. The increase in temperature did not interfere with the interaction constant (Kb ~ 9.37 M-1). Negative values of the standard Gibbs free energy variation (ΔG°) favored complex formation over the free βLG and RES molecules. At lower temperatures, the interaction energy was greater than that of desolvation and conformational change, i.e., the complex formation was driven by the enthalpy. The temperature increase (at 40 °C) was accompanied by the entropic gain (ΔH° = 8.61 and TΔS° = 14.36 kJ.mol-1). βLG-RES formed a stable complex, whose knowledge of the energetics of its nanocomplex formation is important for developing food products focusing in health and well-being.