In this study, the physicochemical properties of chitosan and its use in the ocular drug delivery of vancomycin were evaluated. The physicochemical properties of the chitosan used were characterized in terms of moisture content, degree of deacetylation (DD) and viscosity-average molecular weight (Mv) and were found to be 13.5%, 94.0% and 6.03 × 105, respectively. The vancomycin 50 mg/ml was prepared by reconstituting with Tears Naturale II™, 0.9% sodium chloride and 0.1% and 0.3% chitosan solutions. The antimicrobial potency was measured by the minimum inhibitory concentration against Staphylococcus aureus. The stabilities of the solutions were evaluated by measuring their UV absorption and pH. The results of this study showed that vancomycin 50 mg/ml eye drops in 0.1% and 0.3% chitosan solutions were stable for 28 days when stored at 2-8°C. The main conclusion to be drawn from this study is that the 0.1% and 0.3% chitosan solutions may be useful for the ocular drug delivery of vancomycin due to their biocompatibility, storage stability and cost effectiveness.