We report in this communication the first preparation of triblock copolymer-based biocleavable shell cross-linked (SCL) hybrid micelles using a reducible silica monomer that integrates a polymerizable methacrylate structure and in situ cross-linkers of silica precursors via a disulfide bond. The monomer developed herein offers a highly straightforward and robust strategy toward bioreducible silica-based hybrid nanoparticles for controlled drug release.