Abstract: A catalyst for polymerization, copolymerization and oligomerization of olefins and diolefins is described, which is a compound having the general formula MX.sub.n wherein M is a metal belonging to IVA -- VIA groups of the Periodic System or a cobalt, X is a halogen, hydrogen, cyclopentadienyl, alkoxy-, aryloxy-, or amido group, and n is an integer denoting the valency of M; a compound having the general formula M'R.sub.p Z.sub.k-p wherein M' is a metal of I--III groups of the Periodic System, R is a hydrocarbon radical, Z is a halogen, hydrogen, alkoxy-, aryloxy- or amido group, k is an integer denoting the valency of M', 1.ltoreq.p.ltoreq.k; or compound having the general formula MR.sub.m X.sub.n-m, wherein 2.ltoreq.m.ltoreq.n, said component being chemically bonded with the surface of a carbon-chain polymer carrier through the fragment ##STR1## WHEREIN R' = H, CH.sub.3, C.sub.2 H.sub.5, CH.sub.2 = CH.sub.2, C.sub.6 H.sub.5 ;R" = h, or CH.sub.3 ;R"' = h, or CH.sub.3 ;y = OH, NHR', SR; COCH.sub.3, CH.sub.