Abstract: The possibilities of the mechanochemical synthesis of new fluorine-conducting solid electrolytes based on tysonite and fluorite structures were considered. For the first time, solid solutions in the CeF3–SnF2 system with SnF2 content of 5–30 mol % were synthesized. The possibility of stabilizing the structure of fluorite in solid solutions based on lead(II) fluorine under the conditions of mechanochemical synthesis has been demonstrated.