AbstractCopolymerizations of ethylene with propene, ethylene with 1‐hexene and propene with 1‐hexene were performed at 40°C under atmospheric using three kinds of Kaminsky‐Sinn‐type catalysts which differ in stereospecificity: Cp2ZrCl2‐methylaluminoxane (MAO) (aspecific); Et[IndH4]2 ZrCl2‐MAO (isopecific); i‐Pr(Cp)(Flu)ZrCl2‐MAO (syndiospecific).The 13C NMR analysis of copolymers showed that the incorporation of higher olefins decreases in the following order: i ‐Pr(Cp)(Flu)ZrCl2‐MAO > Et[IndH4]2ZrCl2‐MAO > Cp2ZrCl2‐MAO, and that stereospecificity is retained even in the copolymerization.The product of monomer reactivity ratios (r1 · r2) indicates that poly(propene‐co‐1‐hexene) is a statistically random copolymer whereas both poly(ethylene‐co‐propene) and poly(ethylene‐co‐1‐hexene) have somewhat alternating character regardless of catalyst stereospecificity.