This study was conducted to evaluate the effects of soy hull supplementation on the quality characteristics of fresh lamb from hair and wool × hair sheep lambs. Forty-seven lambs (5-mo old), 23 purebred hair sheep (Barbados Blackbelly or BB, BW = 16.2 ± 1.9 kg; St. Croix or SC, BW = 19.5 ± 2.0 kg) and 24 crossbred wool (Dorset, D) × hair (BB; BW = 21.7 ± 2.3 kg or SC; BW = 21.7 ± 2.9 kg) sheep lambs of both sexes rotationally grazed predominately tall fescue with or without soy hull supplementation during summer. Soy hull was provided at 2.0% of BW at individual feeding stations. After 90 d of grazing, lambs were harvested using standard procedures. After 24 h cooler storage (2°C), longissimus muscle (LM) pH was measured in individual carcasses. Each carcass was fabricated to obtained 2.5-cm thick loin chops for meat quality analysis. All data were analyzed as a completely randomized design with a 2 × 2 x 2 factorial treatment arrangement: breed type (pure- or cross-bred), supplement (with or without soy hull), and sex (male or female). The CIE L* (lightness), a* (redness), and b* (yellowness) values of lamb chops were significantly influenced by supplementation, sex, and their interaction. Chops from supplemented lambs had higher (P < 0.001) CIE a* values than those from grazed-only lambs. The LM from supplemented lambs had higher (P < 0.001) protein (22.4 vs 21.4%) and fat contents (2.88 vs 2.47%) than that from grazed-only lambs. The percent metmyoglobin and thiobarbituric acid reactive substances (TBARS) values of LM from lamb chops were significantly affected by sex, breed type, and breed type × sex. The LM from purebred lambs had a higher (P < 0.05) level of TBARS (0.32 vs 0.27 mg MDA/kg) than that of crossbred lambs. Chops from supplemented lambs had lower (P < 0.01) shear values than those from grazed-only lambs. The results indicate that soy hull supplementation can improve color and texture property of fresh hair sheep lambs grazing fescue pasture regardless of breed type.