The results revealed that different fractions of $Commelina$ $diffusa$ Burm. f. produced significant ($p$ <0.001, $p$ <0.01, $p$ <0.05, $p$ <0.02 and $p$ <0.5) inhibitory activity against the test bacteria and fungi. Methanolic fraction produced the highest zone of inhibition against the test bacteria (11 to 19 mm) which was followed by diethyl etheric extract (3 to 9 mm) and petroleum etheric extract (1 to 2 mm). Again, the methanolic extract showed the highest activity (the lowest MICs; 15.62 to 62.5 ${mu}g/{mu}l$) against seven species among the 11. In case of diethyl etheric and petroleum etheric fractions MICs were found to be (15.62 to 125 ${mu}g/{mu}l$) and (31.25 to 500 ${mu}g/{mu}l$), respectively. The diethyl etheric fraction showed the highest zone of inhibition against the fungi (15 to 19 mm) which was followed by methanolic extract (12 to 19 mm) and petroleum etheric extract (1 to 9 mm). Against the fungi the diethyl etheric extract showed the highest activity (i.e. the lowest MICs; 15.62 to 31.25 ${mu}g/{mu}l$). In case of methanolic and petroleum etheric fractions minimum inhibitory concentrations were found to be (15.62 to 125 ${mu}g/{mu}l$) and (31.25 to 250 ${mu}g/{mu}l$), respectively.