Abstract: Monodispersed thiol functionalized silsesquioxane (PSQ-SH) microspheres were prepared via a copolymerization of methyltrimethoxysilane (MTMS) and mercaptopropyl-trimethoxysilane (MPTMS) monomers in the existence of ammonia. The PSQ-SH microspheres were characterized by Scanning Electron Microscopy (SEM) and Fourier Infrared spectroscopy (FT-IR), and then the adsorption properties of PSQ-SH mircospheres for silver ions were systematically studied. Results showed that the maximum adsorption capacity of PSQ-SH microspheres for silver ions was 750.21 mg/g when the temperature was 25℃ and the initial concentration of silver ions was 0.025 mol/L. The adsorption of silver ions by PSQ-SH microspheres was in accordance with the Langmuir isotherm model, and the adsorption kinetics was more suitable for the pseudo-second order kinetic model. The thermodynamic parameters showed that the adsorption process was endothermic and spontaneous.