In vitro antibacterial activity of a phytoconstituent, entagenic acid isolated from the seed kernel of Entada pursaetha DC was screened against both gram negative and gram positive bacteria. The entagenic acid showed the high antibacterial activity against B. cereus and B. subtilis with minimal inhibitory concentration of 200 lg ml-1 and possesses better glucosamine-6-phosphate synthase inhibition in molecular docking studies with minimum docking energy -9.22 kJ mol-1 , binding energy -9.28 kJ mol-1 and inhibition constant 1.57e-007. The inhibition constant of streptomycin was 3.86e-005.