Abstract: In order to verify that the density and ash of coal fines assume positive correlation,study was made with samples collected from 16 representative process links at Gengyang Coal Preparation Plant. As evidenced by analysis of the relationship between the density and ash of coal fines,the 2 bear a fairly close correlativity. In case the accuracy of calculation of process parameters is not strictly required,the densities of coal fines with different ash contents can well be predicted using the density-ash regression equation of the ＞ 0. 5 mm size fractions.