Provided is an ultraviolet-curable ink jet ink composition with excellent curability and storage stability, the composition containing a monomer A represented by Formula (I): CH2═CR1—COOR2—O—CH═CH—R3 (wherein R1 represents a hydrogen atom or a methyl group, R2 represents a C2-C20 divalent organic residue, and R3 represents a hydrogen atom or a C1-C11 monovalent organic residue); a (meth)acrylated amine compound; a hindered amine compound other than the (meth)acrylated amine compound; and a photopolymerization initiator.