A 54-year-old man was splashed in the right eye with Preeglox-L (a herbicide containing paraquat, diquat, and surfactant). Three days after the topical exposure, conjunctival congestion, corneal edema, and Descemet’s folds were observed. Instillation of 2% topical reduced glutathione decreased corneal edema temporarily. Six days after the exposure marked corneal epithelial defect occurred. Thereafter, the corneal epithelial defect gradually decreased. Topically applied reduced glutathione may be useful in the treatment of the early phase of ocular injury caused by Preeglox-L.