Abstract: One day old broiler chicks (n=240) were used to assess the effect of canola and/or olive oil on performance, immunological and biochemical parameters of broiler chickens fed iso caloric and high caloric diets under a hot climate condition. Birds were divided into 2 groups each of 120 birds based on the level of diet energy as iso caloric and high caloric diet groups. Each group were divided equally into four diet treatments in three replicates, control diet free of examined oils, diet containing 2% canola oil, diet containing 2% olive oil and diet containing 1% canola oil + 1% olive oil. Birds housed in wire cage system in an open house system. Experimental diets started at 15 days old. Weight gain, food conversion, hemoglobin, hematocrite and immune response were determined. Liver and kidney functions were evaluated by assessing the activities of Liver enzymes namely alanine transaminase (ALT) and aspartate transaminase (AST), In addition to kidney function biomarkers (Creatinine, Uric acids and blood urea nitrogen, BUN). Inclusion of canola and olive–canola oils combination in broilers ration increased body weight gain, improved feed conversion and keel length. Both olive and canola oils decreased AST in birds fed iso caloric ration, both oils increased the activity of this enzyme in serum of birds fed high caloric diet. In contrast to canola oil, olive oil did not affect the activity of ALT in birds fed iso and high caloric diets whereas oils combination were not recommended whenever iso caloric diet was available. Moreover, renal function was improved in birds fed ration mixed with olive oil or both oils combination. The examined doses of olive oil was effective than canola oil as feed additives to broilers at the levels of peripheral blood and immune response tested against sheep red blood cells.