High-performance polystyrene-b-poly (ethylene-butylene)-b-polystyrene/thermoplastic polyurethane (SEBS/TPU) blends containing polyurethane blocked styrene-ethylene-butylene-styrene (SEBS-b-TPU) and SEBS-b-TPU/clay were obtained by melt mixing. The influence of SEBS-b-TPU and nanoclay content on morphology, mechanical, thermal, rheological and abrasion behavior of the SEBS/TPU blends were investigated. SEM results indicated that the domain size of the TPU phase was remarkably reduced by the presence of SEBS-b-TPU. Moreover, the addition of clay further improved the extent of mixing. TEM and SEM-EDX revealed that nanoclays were preferentially located in and along the outer edge of the TPU phase with an intercalated/exfoliated structure. TGA results showed that the degradation temperatures (T-5%) were increased by 12.3 degrees C and 20.8 degrees C for SEBS/TPU/SEBS-b-TPU-7% and SEBS/TPU/SEBS-b-TPU/clay-3% nanocomposites, respectively, compared with that of SEBS/TPU. There was also an improvement in mechanical and rheological properties as expected. Meanwhile, the abrasion resistance of SEBS/TPU blends was considerably enhanced by the presence of SEBS-b-TPU/clay, the DIN volume loss decreased by as much as 56%, which can be attributed to the dispersion of the clay platelets in nanoscales as well as the enhanced interfacial adhesion. These superior properties of the SEBS/TPU blends are important for many applications.