Double outlet of right ventricle (DORV) refers to a congenital heart disease in which pulmonary and systemic circulation originates from the right ventricle. In the patient with DORV, it is important to maintain the balance between pulmonary and systemic circulation in anesthetic management. A 4-year-old boy with DORV, who underwent a Blalock-Taussig shunt operation, was transferred to the clinic with a chief complaint of multiple caries. Due to poor cooperability, it was impossible to treat the caries without sedation or general anesthesia. We planned to sedate him with consideration with detrimental effects associated with positive pressure ventilation for dental treatment. After a prophylactic administration of antibiotics, sevoflurane was administered through T-cannula site. Throughout the treatment, His blood remained stable around 80/40 mmHg, oxygen saturation remained around 91%. After 3 hour of sedation with sevoflurane (end-tidal sevoflurane con 1-1.8 vol%), he fully regained consciousness, and discharged from hospital without complications. In case of DORV patient, deep sedation with sevoflurane may be used as effective method of behavioral management during dental treatment.