A hair dye composition which contains components (A)-(C) and has a pH (at 25 DEG C) of 8.5-12, and wherein the mass ratio of the component (B) to the component (C), namely the mass ratio (B)/(C) is from 0.1 to 30 (inclusive). (A) a dye selected from among (A-1)-(A-3) (B) a cationic polymer having a charge density of 3.0 meq/g or more (C) an anionic polysaccharide derivative, wherein: some hydrogen atoms of the hydroxyl groups of a polysaccharide compound having a constituent unit represented by formula (1) are substituted by -(CH2)mCOO- (wherein m is 1-5) the average degree of substitution thereof per constituent unit is 0.5-2.0 and some of the remaining hydrogen atoms of the hydroxyl groups may be substituted by a C1-40 alkyl group and/or an alkylene group (wherein R is a C2-4 alkylene group and n is a number at which the average number of moles of added RO per constituent unit is 0-10).本發明之染毛劑組合物含有成分(A)~(C),且成分(B)相對於成分(C)之質量比(B)/(C)為0.1以上且30以下,pH(25℃)為8.5~12。 (A)選自(Α-1)~(Α-3)之染料 (B)電荷密度為3.0 meq/g以上之陽離子性聚合物 (C)陰離子性多糖衍生物,其係具有式(1)所表示之結構單元之多糖化合物之羥基之氫原子之一部分被取代為-(CH2)mCOO-(m:1~5),其平均取代度為每結構單元為0.5~2.0,其餘之羥基之氫原子之一部分可被取代為C1-40之烷基及/或伸烷基[R:C2-4之伸烷基,n:每結構單元之RO之平均加成莫耳數成為0~10之數]無
