The effects of heated unextracted soybeans (HSB) in diets fed to pigs and rats were studied in three separate experiments. In experiment 1, there were no differences (P> .05) in average daily gain, feed efficiency or carcass measurements between pigs fed diets with solvent extracted soybean meal (SBM) or diets containing ground full-fat soybeans which had been heated to 118 C for 40 minutes.In experiment 2, pigs fed a diet containing soybeans heated to 143 C gained as fast and as efficiently as pigs fed either of two control diets which contained SBM and SBM plus 3.75% animal fat. Pigs fed a diet with soybeans heated to 132 C gained nearly as fast as the control pigs, but they required more (P < .05) feed per unit gain. Soybeans heated to 115 C were undercooked as indicated by lowered animal performance. Pigs which had been fed control diets or diets containing 132 or 143 C HSB had similar carcass measurements while pigs fed 115 C HSB had more (P< .05) backfat and less percent lean cuts. The different sources of soybean protein had an effect (P< .05) on percent of certain fatty acids in backfat and muscle. The HSB diets produced carcass backfat with a lower (P< .05) percent of saturated fatty acids and a higher percent unsaturated fatty acids. Taste panel evaluation of pork roasts indicated no difference (P> .05) due to treatment for muscle flavor, tenderness or juiciness.