The replacement value of dried Erythrina brucei leaf for cotton seed meal (CSM) on growth performance and carcass characteristics was evaluated. Twenty-five yearling buck goats (15.8 ± 1.4 kg) were assigned into five treatments in a randomized complete block design: natural grass hay alone (T1) or supplemented with 100% CSM (T2), 67% CSM + 33% E. brucei (T3), 33% CSM + 67% E. brucei (T4), and 100% E. brucei (T5) on dry matter (DM) basis. Supplemented goats consumed more (P < 0.05) total DM and organic matter (OM) than the non-supplemented group, but the intakes were not influenced (P > 0.05) by the proportion of the supplements. The highest (P < 0.05) crude protein (CP) intake was observed in goats supplemented with CSM alone, whereas the lowest intake was observed in the non-supplemented group. Total CP intake decreased (P < 0.05) with increasing levels of E. brucei in the supplement mixture. The supplemented goats gained more (P < 0.05) weight than the control group. Apparent DM and OM digestibility was higher (P < 0.05) in supplemented goats than in the non-supplemented ones, but similar (P > 0.05) among the supplemented group. The digestibility of CP was higher (P < 0.05) for supplemented goats, except in those goats fed E. brucei alone, than the non-supplemented group. Slaughter weight, empty body weight, hot carcass weight, dressing percentage, rib eye muscle area, and total edible offals were higher (P < 0.05) for supplemented goats than for the non-supplemented ones. It could be concluded that E. brucei could be used as a substitute to CSM under smallholder production systems.