The invention relates to the field of building decoration and particularly discloses a wall surface greening decoration plate comprising a hydroponic plant hanging piece and a base plate. The base plate comprises an upper base plate body and a lower base plate, an inclined channel is formed between the upper base plate body and the lower base plate body, and a groove is formed in the upper base plate body. The hydroponic plant hanging piece comprises a cultivating cup and a cantilever; the cantilever is arranged on the upper portion of the cultivating cup and internally provided with a cavitycommunicating with the cultivating cup, the cavity is internally provided with a floating ball, and a sliding rod capable of being embedded into the groove is fixed to the floating ball; and a siphonis arranged in the hydroponic plant hanging piece, wherein the two ends of the siphon enable the bottom of the cavity and the bottom of the cultivating cup to communicate. A heavy block and an arc-shaped rod fixed to the side wall of the cultivating cup are arranged in the cultivating cup, and the heavy block and the arc-shaped rod are slidably connected. A valve is arranged at the end of the siphon, and a valve seat is fixed to the siphon. A pull rod is arranged in the cultivating cup; the middle of the pull rod is hinged to the cultivating cup, and the upper end of the pull rod is slidably connected with the arc-shaped rod; and a sliding groove is formed in one end of the valve element, and the lower end of the pull rod is embedded into the sliding groove. According to the structure, spilling of water in the cultivating cup can be avoided.