An original technique for the production of an epoxy matrix with chemically bonded metal atoms has been shown to be the hardening of diglycidyl ether of Bisphenol-A (DGEBA) with the chelates of metals salts and organic acids and aliphatic amines. The dependence of mechanical properties of the epoxy-chelate metalliferous polymers on complex hardener structure has been established. For this purpose, the newly introduced idea of “unitized strength” has been used. The structure of the ligands exerts an insignificant effect on the strength and deflection temperature of the polymers. The anions structure alters the deflection temperature over a wide range (90–163°C) but only slightly influences the strength. The deflection temperature (a) and the strength and elongation at break (b) vary depending on the nature of the metal: The optimum set of the strength indices (breaking stresses, elasticity modules, elongation at break, deflection temperature) has been discovered by hardening the epoxy oligomer with 0.49 mol of a chelate per 1000 g of DGEBA (0.17 mol of a hardener per 1 mol of the oligomer). The strength indices decrease as compared to their maximal attainable value of 12%, which makes it possible for a given amount to be used for the evaluation of properties of unknown metal-containing epoxy-chelate compositions.