The average total intake of sodium was 6.11 g in a Chinese urban diet and 6.49 g in the rural sample in China. Discretionary use of salt provided 53% of the total sodium intake in the urban and 63% in the rural diet. Sodium intakes derived from processed foods, soy sauce and monosodium glutamate were 17%, 16% and 6% respectively in the urban diet, and 4%, 16%, 2% respectively in the rural diet. The mean intake of potassium was 1.95 g in the urban and 1.83 g in the rural diet. Cereals and vegetables were the major sources of dietary potassium. The intakes of total sodium, salt and soy sauce decreased as educational level increased. Similar results were found in white-collar workers and blue-collar workers or farmers. Nevertheless, an inverse association between blood pressure and education was found. The results suggest that reduction in sodium intake, especially cooking salt, and increased potassium intake are needed for nutritional control of hypertension in population-based interventions aimed at all social classes.