Inkjet ink composition, an ink set, an ink jet recording method, and printed material

An inkjet ink composition is provided that includes (Component A) a radically polymerizable monomer including at least Components A-1 to A-4, (Component A-1) an N -vinyllactam, (Component A-2) a compound represented by Formula (1), (Component A-3) a compound represented by Formula (2) or Formula (3), and (Component A-4) a di- or higher-functional (meth)acrylate compound and, as (Component B) a polymerization initiator, (Component B-1) a bisacylphosphine compound, the total content of Components A-1 to A-3 being 65 to 90 wt%, the content of Component A-4 being 1 to 9 wt%, and the surface tension at 25°C being 34.0 to 40.0 mN/m.