Calcium hydroxide, widely used in endodontic treatment, is a strong base that may cause irreversible injury to vital tissue that comes into contact with this substance. We present the first case of a dentist who accidentally splashed endodontic calcium hydroxide into her own eye. After washing with copious amounts of water for several minutes, she was treated in the hospital within 30 minutes of the accident. Because of the burning caused by the base solution, the dentist lost vision in the affected eye. She returned to the hospital several times for treatment of a corneal abscess and corneal fungal infection. She had the keloid that formed between the eyeball and eyelid removed 3 times. Calcium hydroxide can cause blindness when it comes into contact with the eye. Clinicians should take adequate precautions to prevent this serious complication. In case of an accident, it is important to wash the eye efficiently.