To address the shortcomings of existing particulate matter trapping technology, especially the low separation efficiency of fine particles, herein, a novel gas cyclone–liquid jet separator was developed to research fine particle trapping. First, numerical simulation methods were used to investigate the flow field characteristics and dust removal efficiency of the separator under different working conditions,and to determined suitable experimental conditions for subsequent dust removal experiments.Afterward, the separation efficiency of the separator against five kinds of common particles, including g-C3N4, TiO2, SiC, talc, and SiO2, was experimentally studied. A maximum separation efficiency of 99.48% was achieved for particles larger than 13.1 μm, and 96.55% efficiency was achieved for particles larger than 2 μm. The best crushing atomization effect was achieved for the separator when uGwas 10 m·s-1and uLwas 3 m·s-1, while the best separation effect was achieved when uGwas 10 m·s-1and uLwas 3.75 m·s-1. Studies have shown that the gas cyclone–liquid jet separator has excellent applicability in the separation of fine particles.