Provided is a surfactant composition capable of securing high fluidity and excellent storage stability while containing a high amount of an internal olefin sulfonate having 16 or more and 18 or less carbon atoms. The present invention relates to a surfactant composition comprising the following components (A), (B), and (C): (A) 45.0% by mass or more 70.0% by mass or less of an internal olefin sulfonate having 16 or more and 18 or less carbon atoms, (B) 0.5% by mass or more 25.0% by mass or less of an alpha-olefin sulfonate having 12 or more and 14 or less carbon atoms, and (C) water, in which the total content of the component (A) and the component (B) is 66.0% by mass or more and 71.0% by mass or less.
