A novel functional polysiloxane (PSBP) bearing benzophenone derivatives as UV absorbing side groups was synthesized by hydrosilylation of polyhydromethylsiloxane (PHMS) with 2-hydroxy-4-(beta-hydroxy-gamma-allyloxy)propyloxy benzophenone (HHAPB). The chemical structure, film morphology, and the softening fabric property of the synthesized polysiloxane were characterized and investigated by spectrum analysis, atomic force microscope (AFM), and Kawabata evaluation system. The experiment results indicated that PSBP was not only an excellent polymeric UV-absorber, which showed intensive ultraviolet absorptions respectively, at wavelengths of 243.2, 288.2, and 325.4 nm, but could exhibit a nonhomogeneous, some rough structure film on silicon wafer substrate. In addition, the functional side group, benzophenone derivative as well as its mass ratio to PSBP has an influence on the performance of the synthesized polysiloxane. As the mass ratio decreased from 31.48 to 12.87%, the molar extinction coefficients epsilon(max) (lambda(max) = 288.2 nm) of the PSBP fluids lowered from 3.4564 x 10(5) to 1.5763 X 10(5), but while the softening fabric properties of PSBP on cotton fabrics increased. (c) 2007 Wiley Periodicals, Inc.