In this project the synthesis and characterization of seven Co(III) Schiff base complexes with possible bio- or electro- and photochemical applications have been discussed. ( 1 ) [Co(Me-saldien)(pprdn)]B(Ph) 4 ( 2 ) [Co(Me-saldien)(prldn)]B(Ph) 4 ( 3 ) [Co(Me-saldien)(mrpln)]B(Ph) 4 ( 4 ) [Co(Me-saldien)(N 3 )] ( 5 ) [Co(Me-saldien)(CN)] ( 6 ) [Co(Me-saldpt)(N 3 )] ( 7 ) [Co(Me-saldpt)(CN)] These complexes have been synthesized in moderate to high yield and are characterized by FT-IR, UV-Vis and 1 H-NMR spectroscopy and elemental analyses. The structure of 1 , 3 , 4 , and 6 have been determined by X-ray diffraction. The correlation between the structure and spectroscopic properties of these complexes are discussed. It seems that the pentadentate ligand is coordinated unsymmetrically to the cobalt centre. Therefore, the methyl groups on the imine carbon of the pentadentate ligand have different chemical shifts and appear as two separate singlets in the 1 H-NMR spectrum. The steric effects on the structural properties of these complexes have been studied and compared with those of the related complexes.