In order to study the wetting effect of C12MImBF4, C12MImBr and C12MImCl on long-flame coal, and their mechanism of action on coal-water bonding, physical experiments, molecular dynamics simulation and DFT theoretical calculation were combined in this work. It is confirmed that the imidazole ionic liquid surfactant optimizes the wetting effect by forming hydrogen bonds, reducing the surface tension of water, and increasing the number of free hydroxyl groups in coal. After the wettability test, the concentration of 4 g/L of the three ionic liquid surfactants had the best wetting effect on long-flame coal, and the contact angle at this concentration was reduced by more than 40 % compared with water within 0.2 s after dripping on the coal. Due to the difference in the anionic head group of the three surfactants, there are differences in the number and strength of hydrogen bonds formed between the three surfactants and water molecules, the results of wettability C12MImBF4 > C12MImCl > C12MImBr were presented. Combined with these characteristics of imidazole ionic liquids on long-flame coal, the reasonable application in the wet dust removal process of actual coal mine production can optimize the efficiency of droplet capture of coal particles, so as to effectively improve the dust removal capacity.