Forty-five weaning male NZW rabbits at 6 weeks of age and an average weight of 655.6 ± 40 g were assigned randomly into 3 equal groups, fifteen rabbits/each for 8 weeks. The study was executed to evaluate the effect of supplementation green coffee extract (GCE) in diets on rabbit growth performance and physiological response. Rabbits in the 1^st group were received a basal diet as a control. While, the 2^nd and 3^rd groups were received a basal diet supplemented with 2 and 4 ml GCE /kg diet, respectively. The results showed an improvement in the treated groups that were fed diets 2 and 4 ml GCE/ kg diets compared with control. Rabbits fed diets with 4 ml GCE/kg diets recorded significantly (P<0.05) higher body weight gain and better feed conversion ratio during all growth period than the control. Dietary with 4 ml GCE/kg diet was significantly higher in carcass weight and total edible parts (%) than that in the control; it also significantly reduced shoulder and abdominal fat. Supplementation of different levels of GCE to rabbits' diet achieved significant increase in beneficial bacteria (total bacterial count and lactobacilli counts) and reduction in pathogenic bacteria (E.Coli clostridium spp and ureolytic bacteria). Also, Hemoglobin, RBCs, WBCs and Hematocrite were significantly higher in groups supplemented with GCE than control. There were no significant differences in total protein, albumin, globulin, A/G ratio, liver and kidney functions and plasma lipid profile between all groups. Catalase activity was significantly higher in blood as GCE added to the diet. Meanwhile, all treated groups decreased insignificantly hydrogen peroxide (H₂O₂) compared to the control group. In conclusion, supplementation of 4 ml GCE/kg diet to NZW growing rabbits improved growth performance, microbial ecology, hematological and biochemical responses and economical efficiency ratio without adverse effects on liver and kidney functions.