Based on the mass screening study for cardiac diseases among schoolchildren, an echocardiographic incidence of a congenital remnant known as the Chiari network was investigated. With two-dimensional echocardiography, we studied 219 schoolchildren. The following conclusions were derived from this study. 1. Incidence of the Chiari network in schoolchildren was 9.5% (21 out of 219). 2. Significantly high incidence of the Chiari network was not noted in the congenital heart diseases group. 3. Male preponderance was noted in both congenital heart diseases and control groups. 4. Parasternal three chamber view was the best way to detect the Chiari network.