Voriconazole is a second-generation synthetic derivative of fluconazole with broadened antifungal spectrum. It is becoming the drug of choice for fungal keratitis. Voriconazole eye drops are not available commercially, thus have to be prepared by diluting the intravenous formulation containing 10mg of voriconazole and 160mg/ml sulfobutylether-β-cyclodestrin sodium (SBECD). SBECD is added to voriconazole to increase solubility, aqueous stability and bioavailability of the drug. The aim of this study was to assess the cytotoxic properties of various concentrations of voriconazole and SBECD on cultured primary human corneal epithelial cells (0.001–2mg/ml). No corneal epithelial cytotoxicity was observed below the concentration of 0.08 and 0.025mg/ml after 24-hour exposure to SBECD and voriconazole respectively. The results of this study reveal the dose-dependent cytotoxic effect of SBECD and voriconazole and thus they recommend that voriconazole eye drops should be used cautiously in the treatment of fungal keratitis.