Provided is a cationic group-containing cellulose which, when incorporated in a hair wash composition, is able to give an excellent smootheness feeling and its sustained feeling in rinsing and give a good coat feeling, and which, when incorporated in a skin cleanser composition, is able to give an excellent moist feeling to the skin after washing and drying, and also provided are a surfactant composition, a hair wash composition, a skin cleanser composition, a hair conditioner composition and a hair treatment composition containing the cellulose ether. [1] A cationic group-containing cellulose ether, which has a main chain derived from an anhydroglucose, and in which the degree of substitution with a cationized oxyalkylene group per the anhydroglucose unit is from 0.01 to 1.0, the degree of substitution with a glycerol group is from 0.5 to 5.0, and the degree of substitution with a group that contains a branched hydrocarbon group having from 8 to 18 carbon atoms and has a specific structure is from 0.001 to 0.2 [2] a surfactant composition containing the cationic group-containing cellulose ether, a surfactant and water [3] a hair wash composition, a skin cleanser composition, a hair conditioner composition and a hair treatment composition containing the cationic group-containing cellulose ether, a surfactant and water.本發明提供一種含陽離子性基之纖維素醚、含有其之界面活性劑組合物、毛髮清潔劑組合物、皮膚清潔劑組合物、毛髮調節劑組合物、及毛髮處理劑組合物,上述含陽離子性基之纖維素醚如下所述:若將其調配於毛髮清潔劑組合物中,則可賦予沖洗時優異之順滑性與其持續感、以及包覆感,若調配於皮膚清潔劑組合物中,則可對清潔、乾燥後之皮膚賦予優異之保濕感。[1]一種含陽離子性基之纖維素醚,其具有源自脫水葡萄糖之主鏈,且每個該脫水葡萄糖單元之陽離子化氧伸烷基之取代度為0.01以上且1.0以下,甘油基之取代度為0.5以上且5.0以下,並且含有碳數8以上且18以下之分支烴基的特定結構之基之取代度為0.001以上且0.2以下;[2]一種界面活性劑組合物,其含有上述含陽離子性基之纖維素醚、界面活性劑及水;[3]一種毛髮清潔劑組合物、皮膚清潔劑組合物、毛髮調節劑組合物、及毛髮處理劑組合物,該等含有上述含陽離子性基之纖維素醚、界面活性劑及水。
