Provided are: a cellulose ether containing a cationic group, which can impart an excellent slipperiness and an excellent long-lasting feeling of the slipperiness during rinsing, excellent smoothness hair upon finger-combing, excellent softness and an excellent coated feeling to hair when added to a hair cleansing agent, and can impart an excellent moisturized feeling after drying to skin when added to a skin cleansing agent and a surfactant composition, a hair cleansing agent composition, a skin cleansing agent composition, a hair conditioning agent composition and a hair treating agent composition, each of which contains the cellulose ether.[1] A cellulose ether containing a cationic group, which has a main chain derived from anhydroglucose, wherein the degree of substitution of a cationized oxyalkylene group is 0.01 to 1.0 inclusive, the degree of substitution of a glycerol group is 0.5 to 5.0 inclusive and the degree of substitution of a group having a specific structure containing a C3-7 hydrocarbon group is 0.0001 to 0.2 inclusive per the anhydroglucose unit [2] a surfactant composition comprising the cellulose ether containing a cationic group, a surfactant and water [3] a hair cleansing agent composition and a skin cleansing agent composition, each comprising the cellulose ether containing a cationic group, a surfactant and water [4] a hair conditioning agent composition comprising the cellulose ether containing a cationic group, a surfactant, an oily agent and water and [5] a hair treating agent composition comprising the cellulose ether containing a cationic group and at least one treating agent selected from a dye for hair dyeing use, an oxidizing agent, an alkali agent and a keratin-reducing agent.La présente invention concerne un éther de cellulose contenant un groupe cationique, pouvant conférer aux cheveux une glissance remarquable, la sensation de glissance se prolongeant tout au long du rinçage, rendant les cheveux extraordinairement lisses après coi
