To improve the anticorrosive performance of polysilsesquioxane coating, the hydroxyl-containing organic-bridged polysilsesquioxane anticorrosive coating was prepared through sol-gel and dip-coating technique, in which the sol was synthesized by acetic acid catalyzed polysilsesquioxane precursor GN. The polysilsesquioxane precursor GN was synthesized by 3-glycidoxypropyltrimethoxysilane (GPTMS) and N-[3-(trimethoxysilyl)propyl]ethylenediamine (NTMDA) through epoxy-amine ring-opening reaction. The anticorrosive performance of the coated Q235 steel specimens was investigated by polarization curve and electrochemical impedance spectroscopy. Furthermore, the effect of aging time on the anticorrosion performance of coatings was investigated. When the aging time was 4 h, its impedance at low frequency of 0.01 Hz increased by 1.5 orders of magnitude in contrast to the bare Q235 steel. In adhesion evaluation test, the coating performed level 1.