Canaliculitis is a frequently overlooked and misdiagnosed disease. Concurrent corneal ulceration with canaliculitis is uncommon. We report such a case.An 87-year-old woman complained of swelling and pain of the right eye after acute angle closure glaucoma attack. Slit-lamp examination was compatible with the features of infectious keratitis, and the cultures from corneal scrapings grew Streptococcus anginosus later. Hourly topical vancomycin (25 mg/ml) was instilled, then the corneal ulceration improved initially but became stationary after 1-week treatment.Discharge from the upper punctum was noted subsequently and canalicular concretions were found through curettage. The cultures from canalicular discharge and concretions also revealed the presence of S. anginosus. Thus, infectious keratitis secondary to canaliculitis was diagnosed.Canaliculotomy was performed to remove the large concretion and vancomycin was injected locally.The corneal ulceration resolved after canaliculitis was appropriately treated.Canaliculitis could be a reservoir for organisms that may make compromised corneas liable to infections. Only the appropriate diagnosis and aggressive treatment of canaliculitis leads to the eradication of associated corneal infections.