Aqueous oil-modified polyurethane dispersions (PUDs) were synthesized using alcoholysis derivatives of vegetable oil, hydroxyl-terminated polyether, isophorone diisocyanate (IPDI) and dimethylolbutyric acid (DMBA). Alcoholysis was performed in order to insert alcoholysis derivatives, which were used as the polyol composition. The structures of alcoholysis derivatives, polyurethane dispersions and their dry films were confirmed by the Fourier Transform Infrared Spectroscopy (FT-IR) and 1H Nuclear Magnetic Resonance (1H-NMR), respectively. The effect of alcoholysis derivatives on the properties of PUD films was investigated. The results show that tack-free time and gloss of PUD films would change with the amount of alcoholysis derivatives. When compared to aqueous polyurethane dispersions, aqueous oil-modified PUDs have shorter tack-free time, higher gloss and tensile strength and lower elongation at broken.