Chitosan, a natural polymer, has been importantly considered as biomedical materials due to its good biocompatibility and various bio-active characteristes. Water soluble chitosan was then copolymerized EGDMA(ethylene glycol dimethacrylate; used as a cross-linking agent for the free-radical copolymerization), MMA (methylmethacrylate), MA (methacrylic acid) in the presence of AIBN (azobisisobutyronitrile) as a radical initiator. The water content and visible transmissibility, ultimate strength of copolymerized ophthalmic polymer were measured to be 24$sim$59%, 88$sim$89% and 0.1$sim$2.4 Kgf, respectively. And also, we tested for antimicrobial activities against staphylococcus aureus, Pseudomonas aeruginosa. They showed that in case of antimicrobial activities, the values including chitosan were much higher than that of the polymers of no including chitosan, suggesting that the copolymer can be used as a novel ophthalmic material of high performance.