Substance abuse is prevalent in adolescent street children, and death is reported as secondary to aspiration, accidental trauma, asphyxia, cardiac arrhythmia, anoxia, vagal inhibition and respiratory depression. In this study, we examined electrocardiographic and echocardiographic findings from 53 street male adolescents, comparing our findings to those obtained from 61 controls in the same age group. The street children smoked cigarettes (98.1%) and had used, or were using, thinner (73.6%), glue (75.5%), hashish (79.2%), morphine or its products (24.5%), ecstasy (37.7%), anti-emetics (13.2%) and alcohol (60.4%). On examination, their blood pressures were lower than the control group. Electrocardiographically, PR, QRS, QT were found to be longer (p less than 0.05) than the values for healthy controls. Although it was not statistically significant, QTc duration was also longer than the control group. Echocardiography revealed increased diameters of the left ventricle and atrium, the aorta, and the coronary arteries as compared to the healthy children (p less than 0.05).