Disclosed is an actinic radiation-curing type ink composition comprising (Component A) a monofunctional radically polymerizable monomer and (Component B) a polyfunctional acrylate oligomer having a glass transition temperature of no greater than 20° C. and having an acrylate equivalent of at least 300 g/eq, Component A comprising (Component A-1) an N-vinyl compound and (Component A-2) an acrylamide derivative, Component A having a content of at least 70 mass % of the entire ink composition, and Component A-1 having a content of at least 18 mass % of the entire ink composition.