A two-part foam hair dye having a first agent containing an alkali agent, a second agent containing hydrogen peroxide, and a non-aerosol foamer container, wherein the first agent contains (A), from 0.20 to 2.00 mol/kg of (B), and 0.05 mol/kg or greater of (Cl)； a total concentration of (Cl) and (C2) in the first agent is from 0.16 to 0.50 mol/kg: and a mixture of the first agent and the second agent has a viscosity of from 1 to 300 mPa．s；(A) a water-soluble cationic polymer,(B) an alkali metal ion,(C1) an oxidation dye having a phenolic hydroxyl group, and (C2) an anionic surfactant.本發明為一種二劑式泡狀染毛劑，係含有含鹼劑之第1劑、含有過氧化氫之第2劑及非氣溶膠起泡容器者，於第1劑中含有成分(A)、(B)0.20~2.00mol/kg及(C1)0.05mol/kg以上，第1劑中之(C1)及(C2)之合計濃度為0.16~0.50mol/kg，第1劑與第2劑之混合液之黏度為1~300mPa．s。(A)水溶性陽離子性聚合物(B)鹼金屬離子(C1)具有酚性羥基之氧化染料(C2)陰離子界面活性劑。
