Argyreia speciosa is a potent medicinal plant in th e Indian systems of medicine. Traditionally it is used as an antibacterial, antifungal, antipyreti c, etc. In the present study the hydroalcoholic extract and its acetone, chloroform and methanol fr actions of the root of A. speciosa were studied for their antibacterial activity by disc di ffusion method against different gram positive (Staphylococcus aureus and Bacilus subtilis) and gr am negative (Escherchia coli) bacteria. It was observed that the hydroalcoholic extract and it s acetone, chloroform and methanol fraction showed significant activity against all the microor ganisms tested here and the hydroalcoholic extract showed the highest activity (13 mm) against S. aureus.