Abstract Two experiments were conducted to determine if fermented corn protein (FCP) can serve as a replacement to enzymatically treated soybean meal (ESBM) in 6.0 to 15.8 kg or as a replacement for soybean meal in 12.1 to 24.7 kg pig nursery diets. In Exp. 1, 350 barrows (initially 6.0 kg) were randomly allotted to 5 treatments with 5 pigs/pen and 14 replications/treatment. Dietary treatments were arranged in a 2×2 + 1 factorial with a control diet or diets with 5 or 10% FCP or ESBM. Newly weaned pigs were fed phase 1 diets for 10-d followed by phase 2 diets for 21-d. There were no interactions throughout the experiment. Overall (d 0-31), pigs fed increasing FCP had decreased (linear, P ≤ 0.026) ADG and ADFI with no differences in G:F, whereas increasing ESBM had no effect on growth performance (Table). Pigs fed ESBM had increased (P ≤ 0.034) ADG and G:F compared with pigs fed FCP with no effect on ADFI. In Exp 2, 350 pigs (initially 12.1 kg) were randomly assigned to pens with 5 pigs/pen and 14 replications/treatment. On d 24 after weaning (d 0 of trial), pens of pigs were weighed and assigned to 5 dietary treatments. Dietary treatments were arranged in a 2×2 + 1 factorial with a control diet or diets with 10 or 20% FCP with either high or low Val+Ile:Leu ratios. There were no interactions observed throughout the experiment. Overall (d 0-21), ADG, ADFI, and G:F worsened (linear, P < 0.001) as FCP increased. High Val+Ile:Leu ratios improved (P = 0.017) G:F compared with low Val+Ile:Leu ratios with no effect on ADG and ADFI. In summary, using FCP to replace ESBM for nursery pigs weighing 6.0 to 15.8 kg had decreased growth performance. Increasing concentrations of FCP in diets for pigs weighting 12.1 to 24.7 kg worsened growth and increasing Val+Ile:Leu ratios only improved G:F.