An ink composition is provided and includes: a dye and at least one polymer of an oxidation-resistant polymer having a weight-average molecula weight of 3,000 or more, an association-accelerating polymer and an amidic polymer. An image printed with the ink composition has an ozone degradation rate of 1/5 or less of that of an image printed with an ink composition free of the at least one polymer. The ink composition has an extremely high image durability.