We report an unusual case of iris rubeosis and hyphema caused by chemical injury due to household detergent. A 74-year-old man with a 15-year history of diabetes mellitus was refilling a container with household detergent at home. He splashed the detergent in his eyes. Slit-lamp examination revealed extensive epithelial damage to the left eye, leading to a persistent corneal epithelial defect. We used a bandage soft contact lens with levofloxacin eye drops as concomitant therapy in order to promote healing. However, a strain of fluoroquinolone-resistant Corynebacterium colonized the eye, so that the corneal ulcer eventually became severe. Use of the bandage soft contact lens was discontinued. His antimicrobial agent was changed to cefmenoxime, a drug to which fluoroquinolone-resistant Corynebacterium is sensitive, and topical instillation of autologous serum subsequently promoted improvement of the ulcer. On day 38 after injury, iris rubeosis led to hyphema and ghost cell glaucoma. With improvement of his corneal epithelial defect, the iris rubeosis and hyphema regressed and his visual acuity improved to 20/25 on the left eye. To the best of our knowledge, this is the first report of a case resulting in severe complications due to chemical injury by a neutral detergent. Ophthalmologists should be aware that corneal epithelial damage may become prolonged in elderly patients with diabetes, and unexpectedly severe when wearing bandage soft contact lens, with infection of Corynebacterium resistant to fluoroquinolones, even if the chemical agent is a neutral detergent.