Provided is a one-part hair dye composition containing (A) one or two or more compounds represented by the formula (1), (B) an antioxidant composed of a combination of ascorbic acid or salt thereof and sulfurous acid or salt thereof, (C) a nonionic surfactant, and (D) a thickening polymer and having a pH of from 8 to 11 and a method of controlling hair color by adjusting an (ascorbic acid or salt thereof) / (sulfurous acid or salt thereof) weight ratio in Component (B) of the composition: (wherein, a broken line: the presence or absence of a À bond, R 1 : OH or acetoxy, R 2 : H, -COOR (R: H, CH 3 or C 2 H 5 ) or -COO - X + (X + : cation), and R 3 : H, acetyl, CH 3 or C 2 H 5 ).
