In order to solve the problem of the waste of semi-coke resources in China, the preparation of semi-coke water slurry with semi-coke powder instead of raw coal can not only alleviate the pressure of oil demand, but also provide a new way for the utilization of semi-coke powder. In this paper, the properties, adsorption mechanism and adsorption kinetics of anionic dispersants were studied by-using Shenfu semi-coke powder and five different dispersants (methylene dinaphthalene sulfonate NNO, sodium lignosulfonate SLS, sodium humate SH, polycarboxylate PCE, complex anion-anion NNO/PCE). The rheological behavior of semi-coke water slurry prepared with each dispersant was studied. The semi-coke water slurry with different dispersants shows pseudoplastic fluid characteristics. When NNO/PCE dispersant is added, the apparent viscosity of the slurry is only 359.3 mPa·s at the shear rate of 100 s-1, and the water separation rate is small without hard precipitation. When NNO is used as dispersant, the fluidity is good, but the stability is poor and the water separation rate is the largest. Through the infrared spectrum test of the semi-coke particle with different dispersants, it is found that the addition of dispersants could change the hydrophilicity and hydrophobicity of the semi-coke particle surface.The adsorption test results show that NNO, SLS, SH, PCE and NNO/PCE reach the adsorption equilibrium at 60,60,120,240 and 240 min, respectively. The increasing trend of adsorption capacity is NNO/PCE (8.796 mg/g)>PCE(7.977 mg/g)>SH(6.845 mg/g)>SLS(3.718 mg/g)>NNO(1.029 mg/g). The pseudo-second-order rate equation can well describe the adsorption kinetics of dispersant on the surface of semi-coke. Finally, the adsorption mechanism model of anionic dispersants was proposed. The results show that the adsorption of anionic dispersants in semi-coke water slurry is mainly due to the enhancement of electrostatic repulsion in semi-coke particles.