The antimicrobial activity testing to evaluated the possibility of S. leucantha for treatment of nosocomial infection such as respiratory tract and urinary tract infections. The aerial part of S. leucantha was extracted using aqueous system with yield of 0.7-1.3% of dried weight of dried plant's powder. The antibacterial activity of S. leucantha aqueous extract has been screened using agar diffusion method. The S. leucantha aqueous extract showed inhibitory effect on growth of L. plantarum ATCC 14917, E. coli ATCC 25922, K. pneumoniae ATCC 10031 and P. vulgaris ATCC 13315. The MICs of S. leucantha are in the rage of 8-16 g L ^-1 while MBCs are in the rage of 16-32 g L ^-1. In conclusion, the aqueous extract of S. leucantha showed inhibitory effect on growth of respiratory tract and urinary tract infection bacteria at low concentration. This result may give supporting data of used S. leucantha as nosocomial infection treatment. © 2009 Asian Network for Scientific Information.