A hair dye composition containing an azo dye (1) or a salt thereof, (wherein R1 to R4 represents H, aliphatic hydrocarbon group, aryl group, halogen atom, acyl group, cyano group, acylamino group, or the like, wherein R1 and R2, and/or R3 and R4 may be coupled to form a 5- or 6-membered ring; X represents C or N, with the proviso that when X represents C, n stands for 1, and when X represents N, n stands for 0; A1, A2, A3 and A4 each represents N or represents C substituted by Y or having H, with the proviso that at least one of A1, A2, A3 and A4 is a nitrogen atom; and Y represents a substituent with the proviso that m stands for an integer from 0 to 3).