The present invention relates to a method for producing a high-molecular-weight copolymer of polar group-containing allyl monomers comprising monomer units represented by formulae (3) and (4) (in the formulae, R1 represents a hydrogen atom (H) or hydrocarbon group having 1 to 6 carbon atoms; R2 represents —OH, —OCOR3 (R3 represents hydrocarbon group having 1 to 5 carbon atoms), —N(R4)2 (R4 represents a hydrogen atom or hydrocarbon group having 1 to 5 carbon atoms); and n and m are a value representing the molar ratio of each of the monomer units), which has few branches and unsaturated group at the molecular end, by copolymerizing olefin and an allyl compound using a metal complex of group 10 elements in the periodic system represented by formula (I) as a catalyst.The present invention enables providing a high-molecular-weight copolymer of polar group-containing allyl monomers, which copolymer has a novel structure, is available for various applications and has been considered to be difficult to synthesize by other polymerization methods such as radical polymerization; and a method for producing the same.