PROBLEM TO BE SOLVED: To provide a hair washing agent composition which has excellent foam elasticity and good finger combing after drying, imparts a moist feeling to hair after drying and has excellent sustainability of hair collectability under a low humidity.SOLUTION: There is provided a hair washing agent composition in which the mass ratio of a component (a) is 1 to 30 mass%, the mass ratio of a component (b) is 1 to 50 mass%, the mass ratio of a component (c) is 1 to 10 mass% and the mass ratio of a component (D) is 0.1 to 3 mass%: (a) an acyl β-alanine based surfactant represented by the formula (1) in claim 1, (b) an acyl taurine based surfactant represented by the formula (2) in claim 1, (c) a polyglycerol fatty acid ester having an HLB of 10 to 18, (d) a cationized cellulose.SELECTED DRAWING: None【課題】泡弾力に優れるとともに、乾燥後の指通りが良好であり、また乾燥後の毛髪にしっとり感を付与し、さらに低湿度下における毛髪のまとまりの持続性に優れる毛髪洗浄剤組成物を提供する。【解決手段】毛髪洗浄剤組成物は、(a)成分の質量比が1~30質量%であり、(b)成分の質量比が1~50質量%であり、(c)成分の質量比が1~10質量%であり、(d)成分の質量比が0.1~3質量%である。 (a)請求項1の式(1)で示されるアシルβ-アラニン型界面活性剤; (b)請求項1の式(2)で示されるアシルタウリン型界面活性剤; (c)HLBが10~18のポリグリセリン脂肪酸エステル; (d)カチオン化セルロース【選択図】なし