The effect of comonomer content and the distribution of side chain branching on thermal, thermal, viscoelastic, rheological, and mechanical properties was investigated using the ethylene 1-octene copolymer (EOC) blends, which consist of one component by the Ziegler-Natta and another by the metallocene catalysts. Two model blend systems were selected; one was composed of FA+FM, which were made using the Ziegler-Natta and metallocene catalysts, respectively, and which has a similar melt index (MI), density, and comonomer content. The other blend was composed of SF+FM, which were also made using the Ziegler-Natta and metallocene catalysts, respectively, however, despite similar MI and density they had different comonomer contents. The big difference between the Ziegler-Natta and metallocene EOC''s is the comonomer distribution and the length of the side chain branching. Regardless of the blending methods (solution and melt blending ), the blends exhibited two distinct melting and crystallization peaks, implying that the constituents excluded one another during crystallization. A single γ relaxation shifted to a lower temperature relative to the content of metallocene EOC, therby indicating miscibility in the amorphous region. In addition, the mechanical properties seemed to have no dependency on the comonomer content. Hence the properties of EOC blends consisting of components with a similar MI and density influenced by both the comonomer contents and the distribution of the side chain branching.