A two-part hair dye including a first part containing an alkali agent, a second part containing hydrogen peroxide, and a non-aerosol foamer vessel to discharge in the form of foam a liquid mixture of the first part and the second part, wherein the liquid mixture contains anionic surfactant(s) selected from the following components (A1) to (A3), or the following components (A4) and (A5): (A1) a carboxylate type anionic surfactant； (A2) a sulfonate type anionic surfactant； (A3) a phosphate type anionic surfactant； (A4) an ionic surfactant； and (A5) a fatty acid alkanolamide.
