The major objective of this study was to determine the fatty acid composition of the Belgian diet. Food consumption data from a large representative sample (n = 11,302) of the Belgian population between 25 and 74 years of age (BIRNH study) were analyzed with regard to the intake of fatty acids. The fatty acid composition of the major fat sources in the Belgian diet was determined and used to calculate average intakes for fatty acids from C4 to C22. In addition, results are compared to other studies and to guidelines for n-3 and n-6 fatty acids. Saturated fatty acids provide 17% of the energy intake in the Belgian diet, polyunsaturated fatty acids 7%, and monounsaturated fatty acids 14%. The intake of total n-6 fatty acids is very high (6 en%), particularly of linoleic acid. The intake of n-3 fatty acids is low, only 0.8 en%, which results in a low ratio of n-3 to n-6 (0.15). The most important sources of n-6 and n-3 fatty acids are margarine and meat, respectively.