Long-term exposure to coal dust can lead to severe health problems in coal workers, including Coal Workers' Pneumoconiosis, making effective control of coal dust in underground mines essential. Water spraying is a widely used method for controlling coal dust, and adding surfactants can remarkably enhance its effectiveness. While previous studies have examined the influences of different coal particle sizes on surfactant performance, they have primarily focused on inhalable dust with sizes less than 100 µm. The impact of finer particle sizes, such as respirable dust with sizes less than 10 µm, remains inconclusive. This study aims to investigate the effects of respirable dust ranging from 0.1 µm to 10 µm in diameter, on the performance of surfactants. It was found that the surfactants' performance was weakened significantly with a decrease in the coal dust size. The suppression efficiency for coal dust size between 0.1 µm and 1.0 µm was only half that of size between 4 µm and 10 µm. The primary factors contributing to this result would be the roughness, the specific surface area, the air absorbability, and the number of particles. Furthermore, TX100 surfactant performed slightly better than SDBS in suppressing coal dust. While SDBS performed greater at a concentration of 0.15–0.20%, TX100 had higher suppression efficiency at lower concentrations. This study suggests that future research should focus on improving the suppressing performance of coal dust with finer sizes less than 0.1 µm or 2.5 µm.