Polysilsesquioxane micro/nanospheres (PSQ M/NPs) are a family of novel organic-inorganic hybrid materials in terms of the unique structure and outstanding performance properties. Beside, they were readily obtained. Therefore, they have the major potential to be used in the fields of chemistry and materials as a hot area of research. This paper reviewed recent synthetic methods of the functional polysilsesquioxane micro/nanospheres and their applications in the domains of luminescent materials, absorbent materials, biomedical materials, flame retardents, and functional coatings. Ultimately, the future developing trend and the existing problems have been proposed in the study of polysilsesquioxane micro/nanospheres.