Fabricated green building roof

The utility model discloses an assembly type green building roof, belongs to the technical field of assembly type roofs, and aims to solve the problem that in the prior art, planted plants are difficult to water and fertilize manually for the assembly type roof, the assembly type green building roof comprises an assembly type roof, and a green plant planting box is arranged on the upper portion of the assembly type roof. A water and fertilizer adding mechanism is arranged above the assembly type roof, the water and fertilizer adding mechanism comprises a supporting seat, watering inclined frames and a water storage funnel, the water storage funnel is arranged on the upper portion of the supporting seat, the two watering inclined frames are symmetrically fixed to the two sides of the supporting seat, and a position adjusting mechanism is arranged at the top of the assembly type roof; through the arrangement of the position adjusting mechanism, when the watering inclined frame is used, the watering inclined fra