PURPOSE: Prenatal diagnosis of congenital heart disease has been made by fetal echocardiography and its clinical impact on the outcome of complete atrioventricular septal defect(AVSD) cases has been analysed. METHODS: A retrospective study was performed for the fetal cases for complete AVSD diagnosed, confirmed postnatally or at second study and/or at autopsy and/or follow up at CHA hospital between January 1993 and December 2001. The outcome of complete AVSD has been analysed, and the associated anomalies & chromosomal defects has been described. RESULTS: There were 450 cases of significant CHD that had been diagnosed prenatally during the study period. Of whom 35 cases had complete AVSD, and 32 cases had complete AVSD associated with visceral heterotaxy. In the cases with complete AVSD who with chromosomal study, 53.8% had Down syndrome and an additional 7.7% had other chromosomal anomaly. Associated cardiac malformation was 34.2%. Extracardiac anomaly without chromosomal defect was founded in 5 cases(14%) included polydactyly, hydrocephalus, duodenal atresia, omphalocele, cleft lip and single umbilical artery. Among 35 fetal complete AVSD cases, 29 cases of complete AVSD has been terminated, 1 case died in utero, 1 case died at neonatal period and 4 cases were referred to cardiac center for planned delivery. The most common factors of termination were extracardiac and chromosomal anomaly. CONCLUSION: Among the significant CHD, incidence rate of complete AVSD was 7.8%. And the most of the complete AVSD has been terminated. 4 cases(11.4%) were referred to the cardiac center for planned delivery. The rate of termination was 82.9%. Fetal diagnosis of complete AVSD greatly increased the rate of termination.