The 1.5 generation hyperbranched molecule was synthesized with dehydroabietylamine as the core by means of Michael addition reaction and amidation condensation reaction with ethylenediamine and methyl acrylate as raws by divergent method.Then,the dispersant was synthesized by means of the 1.5G hyperbranched molecule as initiator by reaction with 2-aminoethanesulfonic acid.The structure of products were identified by IR spectra and 1H NMR spectra.The influences of dispersant on apparent viscosity,rheological behaviour and static stability of coal water slurry prepared from Shenfu coal are studied.The results of the research show that the slurry concentration reach at 67%,and the dosage of the dispersant is 0.4%(quantity fraction of the coal-water slurry),the viscosity of the coal water slurry would be only at 987mPa·s.The rheological investigation indicates that the slurry pumped with dispersant is pseudoplastic fluid.The adsorption curve of hyperbranched dispersant on coal particles approximates L type which has a good adsorptive capacity,and the coal water slurry has a good static stability.