Twenty-seven yearling Tswana steers (BW= 227±11 kg) were divided into 3 groups of 9 animals each in a randomized block design fed finishing diets containing either 30% maize stover, 30% sorghum stover or commercial diet (15% lucerne) to evaluate the effects of roughage sources on feedlot performance and carcass characteristics. Final body weight and average daily gain (ADG) of steers fed commercial diet (418 kg, 2.1 kg) were greater (P<0.05) than those fed on sorghum (381 kg, 1.7 kg/d) and maize stover diets (371 kg, 1.5 kg/d), respectively. Dry matter intake of steers fed sorghum stover diet (9.3 kg/d) was higher (P=0.001) than those fed on commercial (8.4 kg/d) and maize stover diet (8.8 kg/d). Feed efficiency (kg gain/kg feed consumed) was superior in cattle fed commercial diet (4.2) compared to those fed maize and sorghum based diets. The digestibility of DM, NDF and ADF was higher (P<0.05) in steers fed commercial diet followed by maize stover diet. The hot carcass weight and cold dress mass was significantly (P<0.05) different among the experimental diets and was similar in steers fed sorghum and maize stover based diets. Most carcasses from the commercial diet got the super grade (18.52%). The proportions of carcasses that were classified as S1 grade and S2 grade (11.11% and 3.70%, respectively) were similar for maize and sorghum stover diet. The data indicated that inclusion of maize or sorghum stover at 30% level in finishing diets of small-framed breeds like Tswana cattle showed acceptable performance as shown by the proportion of carcass grades. Maize or sorghum stover at 30% in finishing diets elicited similar performance with respect to hot dress mass, cold dress mass, ADG and feed conversion efficiency.