The present study aimed to evaluate the effects of SOD (superoxide dismutase)-rich melon feed supplement on some performance parameters, serum biochemical and antioxidant indexes, and meat quality characteristics of weaned Tuj lambs. An independent measures design (between groups) was used to determine these effects of treatment. After one week of the adaptation period, twenty-four weaned lambs at the age of 60 ± 5.0 days with a body weight of 23.14 ± 0.5 kg were divided into two groups, i.e., the control group (CON) fed basal diet and experimental group (EXP) fed with basal diet + SOD-rich melon (n = 12 per group). The results revealed a decrement in the (p < 0.05) feed efficiency ratio (5.88 ± 0.40 vs. 6.59 ± 0.86 kg weight gain/kg feed) and higher carcass yield (61.76 ± 0.80 vs. 60.11 ± 1.07%) in the EXP group as compared to the CON group. Additionally, the EXP group showed a significant increase (p < 0.05) in serum glucose and high-density lipoprotein levels, while there was a reduction in cholesterol, triglyceride, and low-density lipoprotein levels when compared to the CON group. The serum malondialdehyde was lowered (5.53 ± 0.47 vs. 5.98 ± 0.79 mmol/L) significantly (p < 0.05), while glutathione concentration was higher (p < 0.05) in the EXP group (17.82 ± 1.51 mmol/L) when compared to the CON group (16.54 ± 1.59 mmol/L). The cooking loss was also significantly (p < 0.05) lower in the EXP group when compared to the CON group. In conclusion, the results indicate that SOD-rich melon supplement (30 g/ton of the concentrate feed) can considerably improve carcass yield, some serum biochemical parameters, and meat quality characteristics in Tuj lambs. Thus, the supplementation of lamb diets with a SOD-rich melon additive may be used as an effective nutritional approach to improve their performance and health.