FIELD: organic chemistry, chemical technology. SUBSTANCE: invention describes a novel catalytical system for polymerization of α-olefins including cocatalyst and catalyst which has a chelate compound of transient metal of 4-th group and, at least one, bidentate ligand. As bidentate ligand this system has residue of quinolinehydroxy- or pyridinehydroxy-group of the general formulas (I) 
or (II) 
where Y means O; M means titanium, zirconium of hafnium; each X means independently halogen atom; L means M, cyclopentathienyl or residue of the formula (III) 
where each R' means independently H, C1-C6-alkyl or halogen atom. Invention describes also method of ethylene polymerization and method of polymerization of linear or branched α-olefins. Invention provides possibility to synthesize high-molecular polymers with narrow molecular-mass distribution and sufficient degree of incorporation of olefin comonomers in polymer. EFFECT: increased activity of catalytical system. 7 cl, 2 tbl, 4 ex
