The first aim of this study was to synthesize hyperbranched alkyd resins from tall oil fatty acids and a hyperbranched polyester polyol via an esterification reaction.The second aim was to evaluate the effect of the fatty acid proportion on the properties of the resins.The modification percentage of the hyperbranched polyester polyol was between 47.68 and 66.02%.Infrared analysis shows that the alkyd resins decreased the intensity of the OH group's vibration.This decrease depends on the amount of TOFA used.Thermogravimetric and differential scanning calorimetry analyses showed that the modification of the hyperbranched polyester improved the thermal stability and the mobility of the macromolecules of the alkyd resins respectively.The viscosity of the alkyd resins was less than 10 Pa.s.They exhibited Newtonian behavior and had the highest gloss values at 60° (between 90.1 and 91.6).