The invention discloses a whole-plant corn silage silo. The whole-plant corn silage silo comprises transverse silo walls, longitudinal silo walls and silo bottom ground. A drainage ditch is longitudinally formed in the center of the silo bottom ground. Concrete slatted floors are laid on the drainage ditch. The tail end of the drainage ditch is connected with a non-equi-arm U-shaped pipe. Strip-shaped grooves and long protruding strips are arranged at the positions, at the open end of the silage silo, of the two longitudinal silo walls respectively. Movable concave rubber grooves are laid on the ground at the open end of the silage silo. The open end of the silage silo is sealed through the combination of multiple rectangular blocks. Protruding rubber strips and concave rubber grooves are fixed to the two vertical sides of the rectangular blocks respectively, the rectangular blocks can be combined together and matched for sealing, and after the open end of the silage silo is sealed through the combination of the rectangular blocks, detachable cross rods are installed at the open end of the silage silo and matched with the rectangular blocks to reinforce sealing of the open end.