The invention discloses a core for an engine tail gas evaporation superheater. The core comprises thin-wall large main boards at the two ends, lateral plates on the two sides and a plurality of core modules, and is characterized in that the core modules are each of a stainless steel pipe belt type structure; Freon refrigerants are arranged on the inner side of pipes, and high-temperature engine gas is arranged on the outer side of the pipes; the multiple core modules are arranged in a matrix mode and connected in series at the Freon refrigerant side; and the tail gas and the Freon refrigerants are arranged in an inverse flow mode in the flowing direction. As a superheating area is located at the middle-layer core modules, the problem of high-temperature cracking of the refrigerants can be effectively avoided.