Search for cheap, easily acessable, safe and alternative treatment options is one of the evolving fields in oral health care at present. Acacia nilotica is a plant species that is almost ubiquitously found in diverse parts of the world. The present study investigates the antimicrobial potentialof different solvent extracts (methanol, acetone and aqueous) against Streptococcus mitis, Streptococcus mutans and Prevotellaintermedia. The cytotoxicity of these extracts was evaluated on Vero cells to determine cellular cytotoxicity fifty (CC50). These extracts were subjected to high performance liquid chromatography (HPLC) to determine phenolic acids having antibacterial effects. The outcomes of current study revealed that the methanol extract of A. nilotica showed significantly higher antimicrobial activity in terms ofzone of inhibition (18.00±1.00mm, 20.00±1.15mm and 16.67±0.67mm) and minimum inhibitory concentration (MIC) (0.3125, 0.3125 and 0.15625 mg/ml) followed by acetone and aqueous extracts against S. mutans, S. mitis and P. intermedia respectively. The methanol extract showed higher numbers and quantity of phenolic acids as compared to other solvents. CC50 of the aqueous extract was significantly higher than the other solvents which means it is safest among all extracts for therapeutic purpose.