Five series of cationic polysaccharide Schiff bases surfactant [AQ 10-18 ] were synthesized by the reaction between different five Schiff bases (which prepared by condensation of fatty amine namely: decyl, dodecyl, tetradecyl, hexadecyl and octadecyl amine and 4-pyridine carboxaldehyde) and polysaccharide sulfate as quaternizing agent. Also, their complexes with different transition metals including Ni 2+ , Co 2+ , Cu 2+ and Fe 3+ were synthesized. The chemical structures of these surfactants were confirmed using elemental analysis, FTIR spectra, UV spectra, 1H-NMR and atomic absorption spectroscopy. The studied surfactants were evaluated as antimicrobial agents against pathogenic and sulfate reducing bacteria using inhibition zone diameters. The synthesized cationic polysaccharide Schiff bases surfactant showed good antimicrobial activities against the tested microorganisms including Gram positive, Gram negative, yeast and fungi. The effect of the structure of these cationic surfactants and their metal complexes of Ni 2+ , Co 2+ , Cu 2+ and Fe 3+ on the cell membrane is discussed as well as their potent action on the targeted bacteria, yeast and fungi.