Abstract: Active fractions exhibiting anti-tuberculous activity from the plant Byttneria herbecea (family—Sterculiaceae) are described. Methanol extracts of the aerial part of Byttneria herbecea exhibited activity against MtbGS in primary screening of biosynthetic assay. Subsequent fractionation was carried out in organic solvents. Out of all these, two fractions (fraction D and K) are exhibiting inhibitory activity against M. tuberculosis glutamine synthetase activity. These fractions D and K are inhibiting 74% and 44% respectively at 7.5 mg/ml concentrations. The determined IC50 value of the fraction K is found to be 4.5 mg/ml from the dose response curve against the purified Mycobacterium tuberculosis Glutamine Synthetase. The IC50 value for M. bovis BCG is 1.56 ?g/ml. It was observed that there was no significant effect on proliferation of HL-60 cell line at 10×MIC levels of the hits. This data indicated that these compounds could be initially considered to be safe.