In this study, compatibilization of thermoplastic polyurethane (TPU) and styrene/acrylonitrile (SAN) copolymer blends is investigated after compatibilizer incorporation via melt mixing. Structure examinations performed with transmission electron microscopy (TEM), show that the presence of some compatibilizers reduces the size of dispersed domains and narrows the distribution of domain size. Influence of compatibilizers on viscoelstic properties is investigated by a stress rheoemter (SR-500), where the dynamics tests are performed, Based on the obtained results, it was concluded that the addition of different compatibilizers influences the polymer blend structure and consequently a strong dependence of viscoelastic properties on polymer blend structure was observed. Compatibilized blends show superior properties as compared to non-compatibilized blends.