The complex-formation of the copper(II), rhenium(V) and nickel(II) metal ions with 2-mercaptobenzothiazole (MBT) have been investigated in 1 M hydrochloric acid. The compositions of complexes were determined, and their stepwise stability constants were calculated at 298, 308 and 318 K. The thermodynamic parameters such as, Gibb's free energy change (ΔG), entropy change (ΔS) and enthalpy change (ΔH) associated with the complexation reactions were calculated and discussed. The dissociation process is non-spontaneous, endothermic and entropically unfavourable. The formation of the metal complexes has been found to be endothermic and entropically favourable.