The digestibility of dietary protein by carp, Cyprinus carpio fed for 10 weeks on different levels of chicken gut and duckweed incorporated into the diets was investigated. Growth, food conversion efficiency, protein efficiency ratio and apparent net protein utilization all improved with increase in the level of chicken gut in diet. Generally a linear relationship was found to exist between percentage protein digestibility and level of dietary crude protein. With increase in dietary protein level, protein deposited in tissues increased. However, data from apparent NPU indicate that there is no gain to be made from an excess of protein in diet. Based on this therefore, a recommendation is made as to the optimum combination of chicken gut and duckweed in fish feed formulation. Key words : Cyprinus carpio; duckweed; chicken gut; protein; digestibility Journal of Aquatic Sciences Vol.18(1) 2003: 25-28