Abstract: The aim of this study was to assess the growth performance, hematological and serological assay of broiler chickens given banana (Musa paradisiaca) leaf supplementation. Ninety days-old Marshal straight-run broiler chicks were randomly allocated in a completely randomized design into three treatments, with three replicates per treatment. The treatment groups were denoted as G1, G2 and G3. All chicks were fed ad libitum with same basal diet. Birds on G1 were fed basal diet only (control) whereas, others were fed basal diet supplemented with banana leaf powder and banana leaf infusion at the level of 50 g kg–1 feed (G2) and 50 mL L–1 of drinking water (G3) respectively. Supplementation of banana leaf in the diets of broiler chickens significantly (p<0.05) influenced the final live weight, daily feed intake, daily body weight gain and feed conversion ratio. The banana leaf treated groups had a better performance in all the traits than the control. Mean values of all hematological parameters evaluated (packed cell volume, hemoglobin and red blood cell), except white blood cell, did not differ significantly (p>0.05) between the control and the treated group. Birds in G2 had the highest WBC titre. Reduced glucose level was observed in the treated group. Birds in G2 and G3 had significant (p<0.05) decreases of 54.82 and 46.41%, respectively in serum total cholesterol when compared to the control. Supplementation with banana leaf also significantly (p<0.05) reduced the concentration of low density lipoprotein in the chickens. Though there was an increase in the alanine transaminase, the concentration 16.70 -21.70 IU L–1, was within the normal range for broiler chickens. It was concluded that banana leaf could be safely be used as a phytoadditive in broiler chickens, preferably in the feed.