Trimethyleneditelluro- and trimethyleneoxaditellitro-substituted dimethyl-TTF derivatives were prepared. The CV result of the trimethyleneditelluro-substituted dimethyl-TTF derivative shows characteristic multi-redox behavior and the trimethyleneoxaditelluro-substititted dimethyl-TTFderivative exhibits two pairs of reversible redox waves. The structures and physical properties of conducting salts based on their donors are also clarified.