Four sulfoxide-modified methionine surfactants with different carbon chain length were synthesized from long chain fatty acid and methionine as staring materials. Then, the structure of the products were characterized by means of FTIR, 1HNMR and ESI-MS, and the surface tension, critical micelle concentrations (CMC), emulsifying property, foaming property, hard water stability and antibacterial activity were investigated. The results show that the minimum surface tension of surfactant in this series are below 25 mN/m, the CMC of less than 1 g/L. Moreover, it is indicated that the four kinds of product all have good antibacterial activity against Escherichia coli, Staphylococcus aureus and Candida albicans .