Polymer modified bitumens gain increasing attention in development of durable pavements, resistant to high traffic loads. In-service life of polymer modified bitumens, however, greatly relies on interaction between polymer and bitumen and other pavement components. Consequently, current research is devoted to the development of composition of polyolefine elastomer modified bitumen. Two types of ethylene-octene copolymers (EOC) with different 1-octene group contents have been considered as polymer modifier. The amount of EOC in the bituminous composition has been varied between 1-8 wt.%. Polar compatibilizing agent has been additionally used to increase interaction between polymer and respective bitumen fractions. Rheological (DSR) and structural (FTIR, M-DSC, fluorescent microscopy) properties as well as storage stability of ethylene-octene copolymer modified bitumen have been investigated in comparison to styrene-butadiene-rubber containing composition. It has been determined that selected EOC containing compositions show promising properties for conventional bitumen replacement in pavement applications.