Polyhedral oligomeric silsesquioxane (POSS)/polymer composites have been a hot topic in the field of materials science in recent years. The new organic-inorganic nanoparticle POSS with special cage structure can be used to modify the organic glass (PMMA), which can improve the thermal, mechanical, and flame retardant properties of PMMA, so as to improve the use efficiency of PMMA and broaden its application field. The literature analysis was carried out to clarify the synthesis methods, characteristics, and applications of POSS. And the application of POSS modified PMMA was comprehensively reviewed. This paper analyzes shortcomings of the current research on POSS modified PMMA, and puts forward the key problems to be solved on how to replace tempered glass with POSS modified PMMA in the field of high-rise buildings and traditional transparent material packaging.