Many patients with mental retardation need extensive dental treatment because they have much difficulty in maintaining their oral hygiene. However, because they are not cooperative and not manageable, they require physical restraints, drug induced sedation or general anesthesia. General anesthesia is useful in control of the patients who cannot be treated in other ways. Additionally, general anesthesia provides more safe environment for medically compromised patients. And medical treatment can be provided simultaneously under general anesthesia. Furthermore, almost all treatment can be provided without visiting several times. This case reports of periodontal, restorative and ophthalmological treatment of patient with mental retardation under general anesthesia.