A surfactant composition is provided to show good fluidity at a wide range of temperature even though it contains a polyoxyethylene alkyl ether sulfate or an alkyl sulfate at high concentration, and be free from viscosity increase or gelation when being diluted, thereby being useful for preparing skin washing agents or hair washing agents. The surfactant composition comprises a polyoxyethylene alkyl ether sulfate or an alkyl sulfate represented by the formula(I) of R^1O(CH2CH2O)nSO3M, an alkylene oxide adduct of an alcohol represented by the formula(II) of R^2O-(AO)m-R^3, and a water-soluble salt and is characterized in that it contains more than 40 wt.% of the polyoxyethylene alkyl ether sulfate or alkyl sulfate represented by the formula(I) and has a viscosity of 1,000-70,000mPaÀs at 30 degree. In the formulae(I) and (II), R^1 is a saturated or an unsaturated C8-18 hydrocarbon, n is a number between 0 and 5, and M is an alkali metal, alkanol amine or ammonium, R^2 is a linear or branched C6-10 alkyl or alkenyl, AO is C2-4 oxyalkylene, m is a number between 1-3, and R^3 is H or methyl.폴리옥시에틸렌알킬에테르 황산염 또는 알킬 황산염을 고농도로 함유하고 있어도 폭넓은 온도에서 양호한 유동성을 가지고, 희석시에 점도상승이나 겔화를 일으키지 않고, 계면활성제 본래의 성능을 저하시킬 일이 없는 샴푸, 바디샴푸 등의 피부 세정제 또는 모발 세정제를 제조하기 위해서 유용한 계면활성제 조성물을 제공한다.다음의 성분(A), (B) 및 (C)；(A) 일반식(1)으로 나타내는 폴리옥시에틸렌알킬에테르 황산염 또는 알킬 황산염(B) 일반식(2)으로 나타내는 알코올의 알킬렌옥시드 부가물(C)수용성 염류를 함유하고, 성분(A)의 함유량이 40중량% 이상인 계면활성제 조성물.
