To provide a method for producing a functional group-containing higher α-olefin copolymer, especially a random copolymer.

This method for producing the functional group-containing higher α-olefin copolymer is to bring a metal compound to contact with a functional group-containing vinyl compound to protect the functional group and copolymerize the protected functional group-containing vinyl compound with a 4-20C higher α-olefin in the presence of a polymerization catalyst containing (A) a transition metal compound, (B) a compound capable of forming an ionic complex by reacting with the transition metal compound and/or its derivative and, if needed, (c) an organometallic compound.