We studied the dietary effects of probiotic and fisetin supplementation on performance parameters, carcass characteristics and small intestinal morphology in broiler chickens. Sixty (one-day-old) Arbo Acre breed of broiler chickens were allotted into 4 groups of 15 each randomly: Group I, Control was administered only distilled water; Group II, fisetin (5 mg/kg); Group III, probiotic (4.125×10 6 cfu/100 mL); and Group IV, probiotic and fisetin (4.125×10 6 cfu/100 mL and 5 mg/kg, respectively) for the first one week of life. All administrations were performed orally through gavage. Broiler chickens supplemented with probiotic and probiotic+fisetin had greater feed intake significantly (P<0.05) at weeks 5 and 6, when compared respectively with those of the control and fisetin groups which had lesser feed intake values. Body weight gain was of great significance (P<0.05) in the probiotic-supplemented broiler chickens, while that of the control was less. Carcass quality of the probiotic-supplemented group was higher in significance (P<0.05) than any other treatment group which had lower qualities. The pH changes in the breast muscle was lesser significantly (P<0.05) in the probiotic+fisetin group, when compared with those of the control group which had greater changes. The villus height/crypt height ratio was higher in significance (P<0.05) in the treatment groups, while that of the control group was lower. In conclusion, dietary supplementation of probiotic may enhance broiler chickens’ productivity, by improving performance, carcass weight, pH, and small intestinal morphology as compared to fisetin supplementation.