Fire extinguishing device for building elevator

The fire extinguishing device for the building elevator comprises an elevator car, a water tank is installed on the bottom face of the elevator car, a spraying assembly used for spraying water into the elevator car is arranged on one side of the water tank, a through hole is formed in the bottom face of the elevator car, a filtering assembly is arranged in the through hole, and the filtering assembly is connected with the water tank. A connecting channel communicating with the through hole is fixedly installed at the top of the water tank, and water outlet pipes with upward openings are fixedly installed at the two ends of the connecting channel. After the spraying assembly sprays water to extinguish fire, water flowing downwards can flow back into the water tank through the filtering assembly to be reused, the utilization rate of the fixed amount of water in single-time fire extinguishment is improved, and extinguishing of larger fire behaviors is facilitated. 本实用新型公开一种建筑电梯用灭火装置，包括电梯轿厢，所述电梯轿厢底面安装有水箱，所述水箱一侧设置