This study used different weight ratios of acrylic acid (AA) and chitosan to prepare copolymer, which were then used to produce a variety of hybrid materials by the sol-gel method. Using FTIR and NMR analyses, it was confirmed that the inorganic phase in the hybrid materials is connected to the organic phase by hydrogen bonding. It was also observed that more lumpy aggregates appeared on the surface of hybrid materials when more AA or tetraethyl orthosilicate (TEOS) was added. Hybrid materials were found to be better than composite in swelling, and the property improved when the ratio of chitosan increased. Swelling increased as TEOS concentration increased, but declined when an excess amount of AA was added. Hybrid materials, prepared from an appropriate ratio of AA and chitosan, possessed excellent anti-bacterial property, which had no correlation with TEOS concentration, but decreased when the AA ratio increased.