The study of the valence state, local environment structure and magnetic properties of novel type CuCr 0.99 Ln 0.01 S 2 (Ln = La, Ce) solid solutions was carried out using X-ray absorption spectroscopy, finite difference method simulations and static magnetic susceptibility measurements. The good agreement between experimental and calculated data indicates that cationic substitution does not lead to significant changes in the copper, chromium and sulfur local environment character and electronic density distribution. The copper atoms were found to be in Cu + oxidation state, the sulfur atoms—in S 2− oxidation state and the chromium atoms—in Cr 3+ state. The cationic substitution of chromium by lanthanum and cerium in CuCrS 2 does not significantly affect the effective magnetic moment and exchange interactions character. The lanthanum-doped CuCr 0.99 Ln 0.01 S 2 solid solution demonstrates the Seebeck coefficient value 4 times greater than for CuCrS 2 -matrix at 500 K.