Abstract: The approximate levels of dietary protein and lipid that would sustain good growth and survival of African catfish Heterobranchus longifilis fingerlings were determined in this study. Twelve diets formulated to contain four protein levels and three lipid levels for each protein level were arranged in a 3�4 factorial design. Diets were fed for 56 d to triplicate groups of Heterobranchus longifilis fingerlings with an average initial weight of 0.84±0.03 g. Survival of fish was not affected by either dietary protein or lipid level. Fish fed on diets containing 7 and 12.5% lipid had increased Specific Growth Rates (SGR) up to 35%. Daily feed intake of fish decreased with increasing dietary protein level at all the lipid levels and showed a tendency toward higher values at 7% lipid diets compared to 12.5 or 18% lipid diets at all the protein levels. Feed efficiency of fish fed on 35% protein diet with 12.5% lipid was higher than other groups. However, no significant difference was observed in the feed efficiency of fish fed diets containing 7 and 12.5% lipid with 35% protein. The Protein Efficiency Ratio (PER) of fish increased with increasing protein and lipid levels up to 35% protein with 12.5% lipid. Hepatosomatic and Viscerosomatic index (HIS and VSI) decreased significantly with increasing dietary protein. Moisture content of fish fed 7% lipid diets was higher than those with 12.5 or 18% lipid at each protein level. Lipid deposition in whole body, carcass and liver was higher in fish fed on 18% lipid diets than those fed 7 or 12.5% lipid at each protein level. Significant interaction of lipid and protein was observed in final body weight, feed efficiency, daily feed intake, PER, body protein, body crude lipid and body ash contents of H. longifilis fingerlings. The results of this study indicate that an increase of dietary lipid level can improve growth and PER and the diet containing 35% protein with 12.5% lipid would be suitable for optimum growth and produced protein-sparing effect in Heterobranchus longifilis fingerlings.