Disclosed is a water-based pigment ink composition comprising, as colorants, (1) a surface treated pigment having a water-dispersibility imparting group introduced to the surface thereof and (2) a water-dispersible polymer-encapsulated pigment which is a pigment wholly coated with a polymer. The water-based ink composition exhibits good color developability and satisfactory abrasion resistance, causes little blurring, and has excellent storage stability.