To provide a hair dye composition effective for increasing the solubility of a coupler to a base agent while suppressing the variation of dyeing effect with time.

The hair dye composition is composed of the first agent, the second agent and the third agent. The first agent contains (A) a coupler and (B) a base agent. The base agent B contains (b1) at least one substance selected from surfactants, polyhydric alcohols, ≤4C lower alcohols, polyhydric alcohol ≤4C alkyl ethers and aromatic alcohols. The second agent contains (C) an oxidizing agent. The third agent contains (D) an alkali agent. The octanol/water partition coefficient [log(POW)] of (b1) the surfactant, polyhydric alcohol, ≤4C lower alcohol, polyhydric alcohol ≤4C alkyl ether and aromatic alcohol is within ±3 of the octanol/water partition coefficient of the coupler A.