Objective To obtain a good method for carbon fiber dispersion in the oily substrate. Methods The carbon fibers were firstly processed by dispersants IW, SCAT, MLBH (fatty alcohol ether phosphate salt) and TEDPS, and then dispersed in solvent D80. The surface charge and the turbidity value were used to evaluate the dispersibility, and to analyze the effect of dispersant types or its concentration and the length or concentration of the carbon fiber on the dispersion. The surface morphological structure and chemical composition of carbon fiber before and after leaching silk were characterized comparatively. Results Coating the surface of carbon fibers by different types of dispersing agents could significantly improve the dispersion of carbon fiber in oil material, and fatty alcohol ether phosphate salt (MLBH) was superior to the others. Dispersant concentration showed an optimal value: the longer the carbon fiber, the worse the dispersion; and the lower the concentration of carbon fiber, the better the dispersion. Conclusion Dispersants spread evenly on the carbon fiber surface when the leaching silk concentration of MLBH was 0. 3% (mass fraction), and the dispersion effect was the best. Considering the demand of industrial application, to have the maximum dispersion effect, the dispersion length and the mass fraction of carbon fibers should be 10 mm and 50 mg / L, respectively.