Twenty nine cases, nineteen females and ten males of Noonan's syndrome are reported. The age at diagnosis ranged from five months to 11.5 years (median age: 56 months). Fifteen cases 57% disclose aspects of the Noonan's phenotype in female siblings. Fourteen cases showed an associated cardiopathy. The total included eleven pulmonary valve stenosis, five atrial septal defect. three hypertrophic myocardiopathies, three ventricular septal defect, one patients with pulmonary stenosis manifested an associated situs inversus this concomitance is the first reported in Noonan's syndrome. Eight patients underwent surgery, and two valvuloplasties. We can conclude that Noonan's syndrome includes cardiopathy in 50% of patients the most frequent type is pulmonary valve stenosis. On going follow-up will permit to evaluate the clinical evolution of the hypertrophic cardiomyopathy.