Polymer manufacturing and polymer material usage grows every year. In last decade polymer materials, especially in the form of composite materials, have “conquered” new areas of usa ge. Development of new composites and nanocomposites increase polymer materials perspectives because they are designed to possess enhanced structural, mechanical, thermal, thermo mechanical, rheological and other properties depending on the composition of the multicomponent system. In the current research the effects of anisometric nanostructured fillers (ZnO, smectite clay) on the structure, tribological as well as surface and bulk mechanical properties of amorphous and semi-crystalline thermoplastic polymer blends (polycarbonate/acrylonitrile-butadiene- styrene terpolymer (PC/ABS) and polypropylene/ethylene-octene copolymer (PP/EOC) blends respectively) are investigated. Potential of ZnO nanoparticles to modify stiffness and coefficient of friction of the investigated composites has been evaluated. Roughness of the sample surface has been controlled by using profilometer before and after the pin-on-disk tribological test. Surface of the composites has been investigated by using polarized optical microscopy . Potential of smectite clay nanofiller to modify stiffness of the investigated composites has been also investigated, by paying especial attention to tailoring of interaction between the polymer matrix and nanostructured filler by means of organomodification of the latter. Structure of the obtained polymer nanocomposites has been controlled by means of XRD analysis as well as DSC measurements. By modifying the polymer blend matrix with nanostructured smectite clay it is possible considerably increase elastic modulus and strength of the nanocomposites, especially in the case of the addition of organically modified nanofiller. It has been determined that increment of these stress-strain characteristics is connected with the development of intercalated nanocomposites, confirmed by increased gallery spacing as well as stiffening of polymer macromolecules in the vicinity of clay nanocparticles. By modifying the polymer blend matrix with nanostructured ZnO it is possible to increase stiffness of the investigated nanocomposites. Certain positive effect of ZnO addition on the tribological behavior of the investigated composites has been also observed.