The present invention relates to a method for preparing poly(organic oxidized silicon) particles having UV-absorbing groups, including reacting an organoalkoxysilane precursor having a UV-absorbing group selected from a group consisting of organotrialkoxysilane, diorganoalkoxysilane and a mixture thereof, in the presence of a base, with a silane compound selected from a group consisting of tetraalkoxysilane, alkyltrialkoxysilane, tetraalkoxysilane, aryltrialkoxysilane, dialkyldialkoxysilane, diaryldialkoxysilane, arylalkyldialkoxysilane and a mixture thereof, serving as a crosslinking regulator and UV stability enhancer, so as to prepare poly(organic oxidized silicon) particles selected from a group consisting of polysilsesquioxane, silsesquioxane-siloxane copolymer, silsesquioxane-silica copolymer, silsesquioxane-siloxane-silica copolymer and silsesquioxane-siloxane copolymer, having UV-absorbing groups. The poly(organic oxidized silicon) particles significantly solves the problem of poor UV stability, while maintaining UV absorption by the UV-absorbing group contained in the particles. Since the poly(organic oxidized silicon) particles having UV-absorbing groups do not exhibit white turbidity, they can be effectively used in cosmetics. In accordance with the present invention, the poly(organic oxidized silicon) particles having UV-absorbing groups can be prepared economically as compared to the existing methods.
