Abstract: In view of the extensive application of surfactants in coal flotation,and the surfactants are usually used as promotors in coal flotation. This paper,from another aspect,explores the inhibition effect and mechanism of surfactant on coal flotation under the condition of its excess usage. Using low-ash coal grains and surfactant traverton X-100 as the research object,the adsorption state of travertine X-100 on the coal surface was characterized by X-ray photoelec- tron spectroscopy (XPS),and the static contact angle meter was used to measure the effect of traverton X-100 on the hydrophobicity of coal surface as well as the wetting and spread of different concentrations of travertine X-100 droplets on the surface of coal particles. Induction time measuring instrument was used to analyze the adhesion of bubbles and coal particles in the X-100 aqueous solution of travertine at different con-centrations. Finally,the ultraviolet spectro- photometer was used to quantify the relationship between residual trav-ersing X-100 concentration and the flotation re- sults under various flotation times in flotation cell. The results showed that the high concentration of Triton X-100 will inhibit the coal particles collected and floated by the rising bubble. As the flotation test proceeds,the concentration of Triton X-100 in the flotation cell will gradually decrease,and the low concentration of Triton X-100 will cause the coal particles to be easily floated with the rising bubbles. The high concentration of traverton X-100 could be effective- ly adsorbed on the surface of coal,and the adsorption belongs to physical adsorption. The hydrophobicity of coal sur- face was improved to a certain extent. The high concentration of the travertine X-100 aqueous solution is more condu- cive to wet the coal surface,which slows down the film thinning and cracking rate during the bubble-coal particle ad- hesion process. In a high-concentration travertine X -100 aqueous solution,the surface of the bubble is covered by travertine X-100 molecules,resulting in the modification of the bubble and making it more difficult to effectively ad- here to the coal particles. High con-centration Triton X-100 inhibiting the flotation of coal particles is mainly caused by modifying the bubbles and weakening the film thinning and cracking rate during the bubble-coal particle adhesion process.