Tomato and tomato-by products contain some phytochemicals that may have health benefits and are important sources of many nutrients. Therefore, this study aimed to investigate the effect of two different concentrations (1 and 2%) of tomato powder (TP) in diet of New Zealand white growing rabbits on some physiological, biochemical and histological parameters. Thirty unsexed New Zealand white growing rabbits (42 days old) were randomly assigned into 3 groups (10 rabbits each). The first group served as control (no additives). The second and the third groups were fed diets containing 1 and 2% tomato powder (TP), respectively, for 8 weeks. Results revealed that, no significant differences were observed in the absolute weights of some organs (kidney and thymus) and serum electrolyte concentrations (Ca, P, K, Na) between TP treated groups and control. Dietary 1 and 2% TP supplementation induced alterations in serum biochemical parameters. Serum albumin (g/dl), A/G ratio urea, uric acid and creatinine concentrations were significantly (p < 0.05) decreased by TP administration (1 and 2%), whereas globulin concentration (g/dl) was significantly (p < 0.05) increased compared to control group. Furthermore, no histopathological alterations were recorded in liver and kidney of TP treated groups. In conclusion, TP can be safely used in New Zealand white growing rabbits diet as natural growth enhancer.