An ink composition containing at least water, at least one member selected from a compound represented by formula (1) shown below and a salt thereof, and at least one member selected from an aromatic compound having a carboxyl group and a salt thereof: ##STR00001## In formula (1), A represents a residue of a 5-membered heterocyclic diazo component A-NH.sub.2; B.sup.1 and B.sup.2 each represents --CR.sup.1.dbd. or --CR.sup.2.dbd., or either one of B.sup.1 and B.sup.2 represents a nitrogen atom and the other represents --CR.sup.1.dbd. or --CR.sup.2.dbd.; R.sup.5 and R.sup.6 each independently represents a hydrogen atom, an aliphatic group, an aromatic group, a heterocyclic group or the like; and G, R.sup.1 and R.sup.2 each independently represents a hydrogen atom, a halogen atom, an aliphatic group, an aromatic group, a heterocyclic group or the like.