Abstract: Studies were conducted to determine the influence of the fatty acid composition of the dietary fat supplement on the fatty acid composition of the adipose tissue of broilers. Samples of lard, tallow, poultry oil, and soybean oil, representative of the major source of fats and oils in poultry diets in the United States, were blended in various combinations and fed at 6.34% of the diet in corn-soybean meal broiler finisher diets fed 35 to 56 d of age. Samples of adipose tissue were subjected to fatty acid analysis and regression analysis was used to develop equations for predicting carcass fatty acid composition from the composition of the dietary fat supplement. Highly significant R2 values were observed, indicating that these equations can be used to predict the influence that a particular blend of dietary fatty acids will have upon changes in the fatty acid composition of the adipose tissue of broilers fed diets supplemented with these fats. If sources with markedly different fatty acid structures such as coconut oil, linseed oil, or fish oil are used in constructing the fat blends, these equations may not be applicable.