The authors present a study on prenatal diagnosis of hipoplastic left heart syndrome, and an analysis of the characteristics of a population in a public hospital. The hypoplastic left heart syndrome, and an analysis of the characteristics of a population in a public hospital. The hypoplastic left heart syndrome (HLHS) is a rare congenital heart deficit consisting in the hypodevelopment of the left ventricle, aortic valve, mitral valve and the ascendent aorta. Its incidence is 0,016% to 0.034% of the total of newborns alive. It represents between 1 - 3% of the whole congenital cardiopaties (cc). Its natural evolution is severe and it represents the greater cause of death by CC during the neonatal period. There is a predominance in males between the 55 to 67%. The etiology is multifactorial. Presents risk of recurrency between brothers, and because of that circumstance it could have genetical basis. The ais of this report were to analyze the clinical variables, electrocardiographis, echocardiographic and therapeutical, of a population with diagnosis fo HLHS. The incidence of HLHS in the population studied was 0.06% of life births. The results obtained are detailed (AU)