Dioxomolybdenum(VI) and copper(II) complexes were synthesized using H2L 1 and H2L 2 tridentate Schiff base ligands. The ligands were derived from the condensation 2-hydroxy-4-methoxysalicylaldehyde or 2- hydroxy-4-methoxyacetophenone with 2-aminopropanol, respectively. Both complexes were characterized by physico-chemical and spectroscopic methods. Dimeric nature of the Mo(VI) complexes was revealed by IR spectroscopy. Furthermore, MoO2L 2 (VI) nanoparticles were synthesized by Ultrasonic irradiation.. Elemental analysis, scanning electron microscopy, and FT-IR spectroscopy were used to characterize the nanoparticles. The Schiff base ligands and their complexes have been studied for antibacterial activity against Gram positive and Gram negative bacteria. The results indicated that the Mo(VI) and Cu(II) complexes were effective against all of studied bacteria and its effectiveness was higher for, Escherichia coli.