The structure of medical compression nebulizer plays a decisive role in the atomized inhalation treatment of respiratory diseases. The effects of the nozzle structure, gas flow rate and liquid channel width of the medical compression nebulizer on the atomization effect were studied by the volume of fluid-discrete particle model (VOF-DPM). The results show that the kinetic energy of the droplets after compression atomization and the proportion of droplet size below 5 μm are proportional to the gas flow rate. With the increase of the width of the liquid channel, the kinetic energy of the droplets will increase after atomization, but the proportion of droplet size below 5 μm will be relatively reduced. The use of conical crushing baffle structure can not only improve the kinetic energy of the droplets after atomization, but also increase the proportion of droplet size below 5 μm by about 5%-7% compared with the original. These analysis results have guiding significance for the performance characterization and structural optimization design of subsequent medical compression nebulizers.