Ultrasound research methods were applied in 32 children with the clinical signs of infectious endocarditis (IE). The patients' age varied from 3 to 16 years. In 5 patients, IE turned out primary in the intact valves whereas in 27 patients, it superadded on different congenital heart disease. In 10 patients, IE had developed before surgical correction of the diseases and in 17, within different times after operation. The direct and indirect echo-signs of IE were delineated. The direct echo-signs included vegetations which were discovered in 22 out of the 32 patients. The indirect echo-signs included the signs of regurgitation in the externally unchanged or minimally changed cusps of the valves and blood drop at the level of the ventricles in connection with the defect reshunting in the interventricular septum. The data obtained are in good agreement with the clinical picture, surgical and morbid anatomy data.