Ten herbal plants utilized by backyard poultry raisers in Mt. Apo, Davao del Sur, Philippines were subjected to preliminary testing by veterinary schools in Mindanao. These were investigated for antibacterial and feed additive potential in broiler diets. Antibacterial sensitivity testing of Moringa oleifera Lam. (Malunggay), Euphorbia hirta Lin. (Tawa-tawa), Jatropha curcas Lin. (Tuba-tuba), Azadirachta indica, A. Juss (Neem), Coleus blumei Benth (Mayana), Momordica charantia L. (Ampalaya), Gliricidia sepium Jacg. (Madre de Cacao), Vitex negundo L. (Lagundi), Centenella asiatica (Gotu Kola) and Blumea balsamifera (Sambong) was done. Herbal plants showing antibacterial properties were used in the 42-day feeding trial to determine their effect on the growth of broilers. Antibacterial assay showed highest ZI in Moringa Crude Extract of 23.17 mm and had MIC of 26.32 mg/ml. Average daily feed intake was significantly higher in broilers fed with Moringa Extract-High and Low and Milk Weed Extract-Low. Significantly higher liveweight (1,715.50 g/bird), daily gain (39.72 g) and feed conversion efficiency (2.08 g/liveweight gain) in broilers fed with Milk Weed Extract-High. Highly significant variations on sensory test of meat samples were noted. Results suggested that Milk Weed Extract Diets showed remarkable results in live weight gains and feed conversion efficiency of broilers. This proved that herbal plants could be a better alternative to synthetic antibiotics as antibacterial growth promotant and as a feed additive to broiler diets.