Fabricated building anti-seepage external envelope structure

The utility model relates to an anti-leakage external envelope structure of a fabricated building. An envelope plate comprises a heat preservation layer, buffer layers are arranged on the outer surfaces of the two sides of the heat preservation layer, base plates are arranged on the outer surfaces of the two sides of the buffer layers, and waterproof layers are arranged on the outer surfaces of the two sides of the base plates; two rear sealing strips are movably arranged in the middle of the rear side wall of the enclosure plate, the two rear sealing strips are symmetrically arranged on the two sides of the center line of the enclosure plate, a first extrusion spring is arranged between the two rear sealing strips to form an elastic structure, and the enclosure plate and the rear sealing strips are fixed through fixing bolts; two positioning columns are arranged at the upper end and the lower end of one side face of the enclosure plate in a telescopic mode respectively, positioning grooves matched with the p