The invention discloses a dust removal system and method of flying dust. The dust removal system comprises a jet nozzle, an injection angle regulator, an injection quantity regulator, a pressure sensor, a fluid power system and a control system, wherein the jet nozzle, the injection angle regulator, the injection quantity regulator, the pressure sensor, the fluid power system and the control system are connected in sequence. The dust removal method comprises the steps of collecting pressure information of an operating point by the pressure sensor, and regulating the injection quantity and the injection angle of the jet nozzle, so that a high-speed hedging area of a jet flow field corresponds to a large-particle flying cutting edge of a flying dust field so as to form a certain angle for injection, a negative-pressure entrainment area correspondingly covers a fine flying dust and diffusion area, large-particle flying dust are prevented from flying in a jet hedging mode, fine flying dust and diffusion dust are removed by adopting negative-pressure entrainment and atomizing covering coagulation, and finally, the dust is recovered in a coagulation and settlement mode. According to the system, the diffusion and secondary pollution of the flying dust generated during operation are controlled at the source, so that a good dust removal effect is achieved.