This study aimed to evaluate the influence of the carob powder (CP) and sweet whey powder (WhP) inclusion into weaning feed on the gut morphology, hemato-biochemical parameters, and antioxidant biomarkers. The addition of 10 g/kg (basal diet + 10 g/kg of CP, of WhP) or the mixture (5 g/kg of CP and 5 g/kg of WhP) in the rabbit's standard diet was assessed. A total of 40 weaned New Zealand White rabbits (4 weeks old) was distributed according to body weight (BW) into four treatments (n = 10) and the feed additives were provided for 7 weeks. Tissue samples and blood were obtained after slaughter. Final BW, daily weight gain, feed conversion ratio, intestinal morphology, and carcass dressing were positively affected by CP-WhP treatments compared with the control diet. Also, CP-WhP treatments significantly increased total proteins, calcium and iron levels, fecal cholesterol excretion, total antioxidants capacity, superoxide dismutase, and catalase in different tissues and significantly decreased total cholesterol, triglycerides, and glucose in blood serum. These changes were associated with a diminution of blood tumor necrosis factor alpha, lipid peroxidation, and carbonyl proteins in rabbit tissues. Both the additives separately and especially in the mix may enhance productive performance, protein profile, gut function, immunity, and antioxidant activity, with reducing lipid peroxidation, essential inflammatory mediator, and protein-carbonyl residues of growing rabbits. These findings suggest that CP-WhP dietary supplementation provides novel insights into a variety of bioactive compound mixtures with different beneficial modes of actions.