Fabricated building edge horizontal protection device

The utility model provides an assembly type building edge horizontal protection device which solves the problem that a large high-altitude falling object easily breaks down a horizontal bag net. The device comprises two cantilever beams, each cantilever beam comprises an anchoring section used for being fixed to a structural layer bottom plate and a cantilever section protruding out of the structural layer bottom plate, a vertical beam vertically extending upwards is fixedly arranged at the end, away from the structural layer bottom plate, of each cantilever beam, and the upper end of each vertical beam is fixedly connected with the upper end of an oblique beam I; the lower end of the cant beam I is fixedly connected with the front part of the cantilever section, and the vertical beam, the cant beam I and the front part of the cantilever section form a stable right-angle triangular structure; anti-falling blocking beams are arranged between the cantilever sections of the two cantilever beams and between the t