The invention discloses a dust falling system for ecological environment protection. The dust falling system comprises a street lamp pole, a street lamp body, a solar power generation board and a power storage box, wherein the solar power generation board and the power storage box are arranged at the top of the street lamp pole; a semicircle opening is formed in the street lamp pole, and a fixingboard is arranged on the position, at the lower end of the semicircle opening, in the street lamp pole; a dust falling device is arranged on the fixing board and comprises a transmission mechanism, apipeline and a spray head; the end, connected with the spray head, of the transmission mechanism stretches out of the street lamp pole through the semicircle opening; and a rainwater collecting deviceis arranged at the bottom of the street lamp pole, and the pipeline is connected with the rainwater collecting device through a booster pump. After rainwater is collected by the rainwater collectingdevice, the booster pump is started, and the rainwater enters the spray head through the pipeline; and meanwhile, a motor is started, the motor operates to enable the transmission mechanism to work, the transmission mechanism is fixedly connected with the spray head, thus the spray head also moves along with the transmission mechanism to spray out the rainwater so as to achieve the dust falling effect, and the purpose of ecological environment protection is achieved.