[Problem] To provide a powdered hair dye composition which exhibits favorable mixability between water or the like and a liquid medium, favorable usability when applying to hair, and favorable stability over time when left in over the long term. [Solution] A powdered hair dye composition having the following (A)-(C) components, wherein the amount of the (A) component contained at the time of use is 1-5 mass%: (A) sodium percarbonate (B) carboxymethyl-cellulose sodium and (C) a thickener other than the (B) component.
