North Karelia Youth Project is a community and school-based intervention study of 13-year-old schoolchildren in Eastern Finland. This paper deals with serum total cholesterol, HDL cholesterol and blood pressure levels with some important background variables in the baseline survey in 1978. A total of 966 children were studied. A high mean serum serum cholesterol level (5.1 mmol/l) among both boys and girls was an outstanding finding. The cholesterol level was higher in the rural than urban areas. Different diet can explain this difference. Mean blood pressure was 117/67 mmHg among girls and 117/63 among boys. The high risk factor levels at this age support strongly the idea that the prevention of cardiovascular diseases should be started already in childhood.