Black soldier fly (BSF) oil is a promising alternative lipid source for aquafeeds due to its high lauric acid content, which has antimicrobial properties and potential health benefits for fish. However, excessive inclusion may reduce dietary essential fatty acids, and optimal levels likely vary among species. This study evaluated the effects of replacing soybean oil with BSF oil on growth performance, health, whole-body composition, and heat shock tolerance of juvenile yellow perch (Perca flavescens), an important aquaculture species in the U.S. Midwest. Five diets were formulated by replacing soybean oil (6%) with BSF oil at 0%, 25%, 50%, 75%, and 100%, while maintaining constant protein, carbohydrate, and menhaden oil (5%) levels. Juvenile perch (13 ± 0.09 g; n = 15 per tank) were reared for 9 weeks in a flow-through system (22°C) with three replicates per treatment, followed by an acute heat-shock challenge (22°C to 31°C at 1°C h⁻¹, held for 20 h). Preliminary results showed no significant differences among treatments in weight gain, specific growth rate, feed conversion ratio, or morphology (p > 0.05), and no mortality occurred during the feeding trial. During heat shock, no mortality occurred across treatments, and fish recovered their blood glucose levels and hepatosomatic index following post recovery period, indicating effective physiological compensation. These findings indicate that BSF oil can fully replace soybean oil in yellow perch diets under the conditions tested without impairing growth or feed efficiency. Final conclusions will be drawn after completing analyses of health parameters, nutritional composition, and heat stress response. This study contributes to defining the potential of BSF oil as a sustainable lipid source in yellow perch aquaculture.