A study was conducted to evaluate the growth and carcass performance of sheep under two feedlot finishing diets in Zanzibar. Fifty four sheep (age of 9-12 months with initial body weight 18.9±0.6kg) were divided into three groups (T1, T2 and T3) of 18 in 3 replicates (each having 6 individuals). The sheep in T2 and T3 were assigned randomly to two concentrate formulations (Concentrate 1 and Concentrate 2) and a third group of similar number used as a control (T1) was grazed during the day and given no supplements. All animals in T2 and T3 were offered 600g/day concentrates and basal roughage feed of Brachiaria decumbens, Pennisetum purperium and Gliricidia sepium mixed at a ratio of 1.2:1.2:1 respectively at ad libitum level. The concentrates’ principal energy ingredients were rice bran and wheat pollard included in the compounded concentrates as respectively 35% and 25% in T2 and 40% and 20% in T3 while holding all other components constant. Feeding was done for 82 days after which 6 animals were randomly picked from each treatment and slaughtered for carcass analysis. In addition a panel test was run to assess acceptability and ranking of mutton against common beef and goat meat by consumers in Zanzibar. The results of this study revealed that average daily gain of 19.8±4.92, 90.2±3.94 and 85.7±3.85g/day for T1, T2 and T3, respectively. However, there were no significant difference on feed intake and growth performance for T2 and T3. Empty body (23.24 vs. 21.38kg) and hot carcass weight (11.52 vs. 10.87kg) were not significantly (P>0.05) different among T2 and T3. All carcass parameters in sheep on T2 and T3 were similar between them but were significantly superior (P<0.05) to those on T1. Finding from the taste panel showed that mutton was ranked higher than beef and goat on its merits of superior aroma, flavour, juiciness and softness. A good number of consumers were able to identify mutton from goat meat. The cost-benefit analysis showed that carcasses from sheep on T2 had higher net income of Tsh 41,453.68 iii compared to those from T3 and T1 (Tsh 35,223.70 and 8,293.04) respectively. It is concluded that the formulation Concentrate 1 containing rice bran and wheat pollard at a ratio of 1.4:1 in favour of rice bran can profitably support an average daily gain (ADG) of at least 90.2g for sheep entering the feedlot at 18kglive weight. It was also shown that mutton can be readily acceptable to consumers if animals are raised to produce carcases of superior quality.Commission for Science and Technology and Kizimbani Agricultural Training Institute (KATI)