This experiment was conducted to examine the effect of neem (Azadirachta indica) as an antibiotic growth promoter substitute on growth performance, carcass traits, and humoral immune responses in broiler chickens. A total of 192 one-d-old mixed sex broiler chicks (Ross 308) were weighted and randomly allocated to four treatment groups, each with 4 replicate pens of 12 chicks. The dietary treatments consisted of the basal diet (control), control+4.5 mg flavophospholipol/kg, or control+7 or 12 g neem fruit powder/kg.