A total number of 60 weaned male and female V-line rabbits were used to evaluate supplemented Amphora coffeaeformis (A. coffeaeformis) alga extract (ACE) in drinking water on productive performance, carcass traits, physiological and antioxidant status during hot conditions. The experimental rabbits were randomize divided into four equal groups (n=15 each). In the first group (C), rabbits were kept as control (drank water without additives), in the 2nd group rabbits drank water supplemented with vitamins and minerals (1 ml/liter, T1), in the 3rd group rabbits drank water supplemented with 0.5ml ACE (0.5 ml/1iter, T2) while in the 4th group rabbits drank water supplemented with 1ml ACE (1 ml/liter, T3). Body weight and total feed intake were weekly recorded. Total body gain, feed conversion were calculated and carcass traits of rabbits were also measured. Blood hematological, metabolites and antioxidant biomarkers were determined. The results showed that no significant differences were observed among groups in concern final body weight or body weight gain, carcass or internal organs weight percentages, blood hematological parameters and indices. While, 0.5 and 1ml ACE recorded significantly the best antioxidation indices (MDA and Catalase). Supplementation of rabbit drinking water with A. coffeaeformis alga had positive impact on performance and antioxidant capacity of growing rabbits under heat stress condition.