Reaction of Cp 2 VCl 2 with α-amino acids bearing functional group in the side chain gives N,O-chelate complexes [Cp 2 V(N,O-aa)]Cl (aa=ser, thr, asp, glu, asn, gln, lys, arg). These complexes were studied by spectroscopic methods (ESR, IR and Raman). All prepared complexes contain amino acid ligand bonded via oxygen atom of carboxylic group and nitrogen atom of amino group in α-position giving five-membered chelate ring. We have observed that hydroxy, amine, carboxylic, amide and guanidinium groups present in α-amino acid ligand are not able to coordinate to the central vanadium atom.