From October, 1960, to December, 1976, a total of 167 patients with the tetralogy of Fallot (TOF) underwent corrective repair under simple deep hypothermia at Iwate Medical University. In 59 out of 167 patients the address or telephone number were identified. Fifty-four patients, consisting of 25 males and 29 females, were investigated by written questionnaire or telephone interview. They were followed for 20-35 years. The mean (±SD) age at operation was 5.3± 4.2 years old (range 6 months to 19 years). Reoperations were successfully performed on two patients with residual shunts. Among these, 43 patients (80%) were in NYHA class I, and 11 patients (20%) were class II. None of the patients were in class III or IV. Medication was not prescribed except in one patient. Twenty-eight patients (52%) married and gave birth to 34 children, none of whom had congenital heart disease. A total of 51 (94%) patients were employed, or were housewives. In conclusion, most patients were considered to have a good quality of life long after repair of TOF under simple deep hypothermia.