Electric bidet toilets are automatic devices that deliver water jets to clean the anus. Although the use of bidets to clean the anus after defecation contributes to hand hygiene and local comfort, excessive use may cause anal pruritus and incontinence. However, no cases of anorectal aphtoid ulcers caused by bidet use have yet been reported in literature. A 61-year-old woman presented to our hospital with anal bleeding and pain. Anoscopy revealed an aphtoid ulcer in the anterior midline anorectum. She reported using a bidet toilet and washing her anus before and after defecation for one year. The frequency of washing was five times or more per day, the force of the water jet was strong, the thickness of the water was thin, and the duration of washing per use was 1 min or more. She responded well to the advice of stopping bidet use. At the follow-up, 5 weeks after discontinuing bidet use, she became asymptomatic, and the anoscope showed that the aphtoid ulcer had completely healed. The water jet of the bidet toilet seemed to be the causative factor for the anterior aphtoid ulcer in the anorectum.