To identify the antimicrobial activity of tumeric and its active compound tumeric was fractionated into four groups dichloromethane extract, hexane fraction, methanol soluble fraction and residue's extract. They were tested for antibacterial activity against E. coli and S. aureus and the methanol soluble fraction was found to be the most active fraction. Compound Ⅰ, Ⅱ and Ⅲ were isolated from TLC and silica gel column chromatography in the methanol soluble fraction. These compounds were analyzed by 1H-NMR and 13C-NMR spectra and identified as curcumin Ⅰ, Ⅱ and Ⅲ. They were also tested for antimicrobial activity against E. coli and S. aureus. Curcumin Ⅰ was the most active curcuminoids due to the phenolic and methoxyl(OCH3) moiety in the same molecular structure.