The polymerization stability and the chemical stability and the water resistance of resin films are improved. A surfactant composition according to an embodiment contains a surfactant (A) represented by general formula (1) and an anionic surfactant (B) having a hydrophobic group different from that of the surfactant (A). R1 represents an alkyl group with 8 to 14 carbon atoms, A represents an alkylene group with 2 to 4 carbon atoms, and n representing an average number of moles of an oxyalkylene group added represents 1 to 100.