Argon ions of a kiloelectronvolt energy were irradiated on saturated simple-chain polymers. such as polyethylene (-CH2-CH2-)(n), poly(vinylidene fluoride) (-CH2-CF2-)(n), and poly(tetrafluoroethylene) (-CF2-CF2-)(n) in an oxygen environment. Irradiating ions have induced chemical changes in polymeric chains, which includes substitution reactions for environment gas species resulting in the formation of radicals, carbonization, and bond scission bur, exceeding the optimum ion dose, a carbonized phase was formed on the polymer surface. The relationship between the surface chemical reaction and the formation of hydrophilic polar groups was investigated with a view of the compositional change on the polymer surface and the kinetic energy of ions. From experimental result,. identification of newly formed bonds and chemical changes depending on the depositing energy of the incident ions is represented.