New fluorinated silicon oligomers containing carboxy groups were prepared by the reactions of fluoroalkanoyl peroxides with acrylic acid and trimethylvinylsilane. These fluorinated silicon oligomers were found to indicate surface properties typical of the amphiphilic compounds and to be easily soluble in both water and aromatic solvents such as benzene, toluene, and m-xylene. Moreover, these oligomers were able to reduce the surface tension of these solvents effectively.