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.
