Abstract: Feeding trial was conducted in static water to assess the growth and nutrient utilization of Heterobranchus longifilis fingerlings fed Mucuna Seed Meal (MSM). Raw and boiled MSM were used at 10%, 20, 30 and 40% inclusion levels to formulate isonitrogenous (CP 40%) and isocaloric (2.8 Kcal g ¹) diets similar to a fishmeal-based control diet. It was observed that after 8 weeks of feeding at 5% body weight daily, diets 2 (10% raw MSM), 6 (10% boiled MSM) and 7 (20% boiled MSM) performed well with SGR, AFCR and APER that were similar (p< 0.05) to the control diet (1) which was significantly different from the other diets. While the fish carcass fat showed similar trend as the SGR, AFCR and APER for the MSM containing diets, the carcass protein for all fish fed diets containing boiled MSM had similar values as the control diet. The significantly lower performance of fish fed diets containing higher levels of MSM might be due to the increasing levels of antinutritional factors present in particularly raw MSM and the lower quality of boiled MSM arising from both heat treatment and thermostable antinutritional factors. Other methods of processing MSM to improve its nutritive value should be investigated.