As an excellent UV absorber, zinc oxide nanoparticles (ZnO Nps) are limited applications in anti-photofading coating fields due to the high photocatalytic degradation activity, which can accelerate dyed fabrics fading. Herein, a “core-shell” shaped composite nanoparticles with high UV absorption and low photocatalytic degradation properties were successfully fabricated by encapsulating ZnO Nps in polyhedral oligomeric silsesquioxane (POSS) via the alkaline hydrolysis method, and then the POSS coated ZnO Nps (ZnO@POSS Nps) were applied as UV absorber to improve the photostability of dyed polyester fabrics. Field emission scanning electron microscope, Fourier transform infrared spectroscopy and X-ray diffraction analysis confirmed the strong relevance between the POSS shell thickness and micromorphology and structural interface characteristics of “core-shell” shaped ZnO@POSS Nps.