Disclosed is a surfactant composition which contains a cationic surfactant (hereinafter referred to as compound (A)), one or more compound selected from the group consisting of anionic aromatic compounds and bromide compounds (hereinafter referred to as compound (B)), and a cationic polymer (C). The viscosity at 20 DEG C of a solution mixture, wherein a water solution SA of the compound (A) and an equal amount of a water solution SB of the compound (B) are mixed, is at least twice as high as respective viscosities of the solutions SA and SB (at 20 DEG C) before mixing.