An ink composition is provided that includes (A) an N-vinyllactam, (B) a monomer represented by Formula (I), and (C) a radical polymerization initiator, or includes (A) an N-vinyllactam, (B) a monomer represented by Formula (II), (C) a radical polymerization initiator, and phenoxyethyl acrylate. ##STR00001## (In Formula (I) and Formula (II), R.sup.1 denotes a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbons, X.sup.1 denotes a divalent linking group, R.sup.2 and R.sup.3 independently denote a substituent, k denotes an integer of 1 to 6, q and r independently denote an integer of 0 to 5, n denotes a cyclic hydrocarbon structure, the cyclic hydrocarbon structure may comprise in addition to hydrocarbon bonds a carbonyl bond (--C(O)--) and/or an ester bond (--C(O)O--), and the k R.sup.1s, the k X.sup.1s, the q R.sup.2s, and the r R.sup.3s may each be identical to or different from each other; furthermore, one carbon atom in the adamantane framework in Formula (I) may be replaced by a carbonyl bond (--C(O)--) and/or an ester bond (--C(O)O--), and one carbon atom in the norbornene framework in Formula (II) may be replaced by an ether bond (--O--) and/or an ester bond (--C(O)O--).) There are also provided an inkjet recording method, a printed material, and a process for producing a lithographic printing plate that employ the ink composition.