Ternary vapor-liquid equilibria (VLE) of selected aqueous azeotropic systems in the presence of differently branched hydroxyl functional components (additives) have been measured. Three azeotropic mixtures, ethanol + water, 2-propanol + water, and tetrahydrofuran + water, were chosen. The additives used were non, volatile hyperbranched polymers such as polyesters, polyesteramides, and polyethers as well as low-volatility alcohols (1,2-ethanediol, 1,4-butanediol, 1,6-hexanediol, 1,12-dodecanediol, 1,2,3-propanetriol, 1,2,3,4-butanetetrol, and 2,4-dimethyl-3-pentanol). The experimental results show the influence of differently structured additives, that is, their degree of branching, molecular weight, and number of functionalities, on the VLE of the respective azeotropic system. For the investigated polymer solutions, the extent of inter- and intramolecular hydrogen bond formation has a dominant impact on the solvent activity and therefore determines the partition coefficients and the relative volatilities. Due to their remarkable solution properties, hyperbranched polymers such as hyperbranched polyesteramides or hyperbranched polyglycerols can be used for the separation of azeotropic mixtures by means of extractive distillation.