In DR Congo, broilers are increasingly popular, their diet requires a certain protein balance. Cowpea seeds are particularly rich in protein (23 to 25 of their dry weigh), carbohydrates (50 to 67%) and lipid (1,9%). The objective of this article is to improve the diet of broilers by substituting soybeans for cowpea seeds in Kabinda. Three batches of 30 chicks to 15 days were feed rations based Cowpea seeds, Chicken feed 0% control (T0), chikens feed 10% cowpea (T1) and chikens feed 20% (T2). The results obtained on the average daily earnings varied betwen 56 and 160g thraught the experimental period. The effect of substituting soybeans with cowpea seeds were remarkable in the third and fifth week of observation. However, chickens subjected to 20% cowpea (T2) presented a GMQ superior of 160g contrary to the control chickens (T0) is 98. The use of all diets resulted in much more remarkable performance influences for protein-rich rations. It emerges from this study that soybeans can be replaced by roasted cowpea seeds in chicken feed in Kabinda.