The application relates to a green building wall, comprising a base wall, the base wall is provided with an external frame, the external frame is provided with a green exterior wall panel, the green exterior wall panel is provided with a planting groove, and the bottom wall of the plantation groove is provided with an oblique partition board, the green exterior wall panel is provided with a water storage chamber, the base wall is provided with a water supply pipe, the inner wall of the water storage chamber is provided with a float valve, and the inner wall of the communication channel is provided with a filter core. The green exterior wall panel is provided with a grid plate, the grid plate is provided with a grid hole, the inner wall of the grid hole is provided with a water expansion ring, the green exterior wall panel is provided with an embedding groove, and the green exterior wall panel is provided with a splicing groove, sliding The inner wall of the sliding hole slides and is provided with a slide bar, and the green wall panel is provided with a driving mechanism. The driving mechanism includes a worm, a worm wheel, and a threaded rod. By setting inclined partitions, water storage chambers, and connecting pipes, the green building wall can stably supply water to the plants on itself, so that the plants are not easy to wither due to water shortage; by setting grid plates and water expansion rings, rain can be reduced , the amount of water entering the planting area.