A catalyst composition for hydrogenation including (A) to (D), in which a mass ratio (D)/(A) is 0.01 to 2.00. (A): a titanocene compound represented by following formula (1), (wherein R5 and R6 are selected from the group consisting of hydrogen, a hydrocarbon group having 1 to 12 carbon atoms, an aryloxy group, an alkoxy group, a halogen group, and a carbonyl group, and R1 and R2 are selected from hydrogen and a hydrocarbon group having 1 to 12 carbon atoms) (B): a compound containing an element selected from Li, Na, K, Mg, Zn, Al, and Ca, (C): an unsaturated polymer having a fraction of an olefinic unsaturated double bond content of side chains based on a total olefinic unsaturated double bond content of 0.25 to 1.0, and (D): a polar compound.