This study evaluated the effects of muscle and dietary treatments including CORN, dry distillers grains (DDGS), and modified distillers grains (MDGS) on fatty acid deposition in two novel value-added beef cuts (Petite Tender - M. teres major - TM, and Flat Iron – M. infraspinatus - INF). Crossbred steers were randomly assigned to one of three dietary treatments (CORN, 40% of DDGS with 8-12% of moisture, and 40% of MDGS with 45-55% of moisture - DM basis) and fed for 190 days. The TM muscle had higher concentrations of ω6 fatty acids and PUFA when compared to INF. Beef fed CORN showed greater C16:0 and lower C18:0 values when compared to beef fed DGS. Beef fed DDGS had higher concentrations of ω6 fatty acids when compared to MDGS. Different moisture levels only affected fatty acids containing 14, 16, and 17 carbons. Different muscles, diets, and moisture levels of DGS affected the deposition of fatty acids in the lean.