Abstract: In order to investigate the oil adsorption and desorption properties, the oil-absorbing cotton used for electronic cigarette wick was modified by dopamine and mesoporous silica materials. The modified cotton, on which the polydopamine adsorbed, was obtained by immersing the oil-absorbing cotton in dopamine aqueous solution. The dopamine-modified cotton further adsorbed mesoporous silica material by using toluene diisocyanate as coupling agent. The abilities of oil adsorption and desorption of the two kinds of modified oil-absorbing cotton were measured through weighing and thermogravimetric analysis. The results showed that:1) The saturation adsorption of dopamine-modified oil-absorbing cotton increased by about 50%. 2) It was further promoted by 8.57% and 3.23% after the dopamine-modified cotton was modified by large aperture or small aperture mesoporous materials, respectively. 3) The complete desorption temperatures of the modified oil-absorbing cotton rose a little, but were still under the decomposition temperature of oil-absorbing cotton, 275℃. It indicated that the desorptive release of electronic liquids was complete before the decomposition of oil-absorbing cotton.