Molybdenum (V) and (VI) complexes of novel ligand 2,6-diformyl-p-cresolbis [4-(X-phenyl) thiosemicarbazone] (where X=−H,o-CH3,m-CH3,p-CH3,p-OCH3 andp-Cl) are synthesised and characterised on the basis of elemental analyses and magnetic, IR, UV, EPR, and NMR spectral studies. The complexes have the composition [MoO2LH] and [MoOClLH]. The Schiff bases behave as dibasic tetradentate SNON donor ligands.