This study aimed to examine the effects of food supplementation with varying amounts of phytase on growth performance, nutrient digestibility, and blood parameters of growing rabbits in summer settings in Egypt. An experimental design was conducted incorporating three levels of phytase: 0.0, 1.5, and 3.0 g/kg of food, along with a control group, during the winter season. Results demonstrated that growth performance, daily feed intake, feed conversion ratio, nutritional digestibility, nutritive values, hemoglobin, hematocrit, alanine aminotransferase (ALT), and red blood cell counts were considerably diminished throughout the summer season in comparison to the winter control. Conversely, phytase levels significantly enhanced growth performance indicators, crude fiber (CF) and ether extract (EE) digestibility, as well as other blood parameters including aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea, triglycerides, and cholesterol in growing rabbits. In conclusion, the findings indicated that the fortification of rabbit diets with phytase, particularly at levels of 1.5 and 3.0 g/kg, could improve the growth performance of rabbits during mild and hot climates in Egypt.