Abstract: Equilibrium constants for the formation of Co²⁺,Ni²⁺,Cu²⁺,Zn²⁺and Cd²⁺bis-complexes of asparagine have been determined potentiometri-cally at an ionic strength of 0.1 and at 10°,15°,20°,25°,30℃.At all the temperatures studied,the Gibbs free energy changes increase in the Order Cu²⁺<Ni²⁺<Zn²⁺<Co⁹⁺<Cd²⁺.The enthalpy and entropy changes for the bis-species are calculated from the temperature coefficient data.The primary driving force favoring the formation of the corresponding complexes in solution has been discussed.