The invention discloses a double-layer electrode for a multi-level depressed collector and a preparation method thereof, and relates to vacuum device technology. The double-layer electrode comprises a metal layer and a graphite layer; opposite surfaces of the two layers are fixedly connected tightly; and the material of the graphite layer is pyrolytic graphite or high-density isotropic graphite. The electrode can ensure air-tight seal with ceramics and other metals by utilizing the outer-layer electrode; and the inner-layer pyrolytic graphite or high-density isotropic graphite has low secondary electron yield so as to facilitate improving the efficiency of the multi-level depressed collector. The preparation process adopts coating and sintering technology, and is simple and firm.