Cardanol, a naturally occurring C15 unsaturated aliphatic chain substituted phenol derived from cashew nut shell liquid (CNSL) was used for the preparation of polymeric Schiff base ligand using ethylenediamine. This preparation involved (a) the conversion of cardanol into bis(3-pentadecenylphenol) methane (BPPM) using formaldehyde. (b) bis(3-pentadecenylphenol) methane into di-a-formylmethoxy bis(3-pentadecenylphenyl)methane (DFMPM) on treatment with epichlorohydrin followed by the action of sodium periodate. (c) DFMPM to (2+2) macrocyclic Schiff base ligand with ethylene diamine and finally (d) Schiff base complexes with transition metal salts. The ligand and complexes were characterized by IR, UV-visible, 1H NMR and elemental analysis, melting point, conductivity, metal ion intake and the antibacterial activity were studied. The conductance measurements indicate that all the complexes of nonelectrolytes. The infrared spectra indicate the coordination of imino nitrogen and M-N bonds. UV-visible spectra provide structural details of these complexes. 1H NMR data is also consistent with IR spectral data. The results indicate that the complexes of Cu(II), Ni(II) and Co(II) are hexacoordinated and have moderate antibacterial activity. The metal ion intake indicates the ligand can be used for the extraction of these metals from water.