Abstract: The macerals of 24 Chinese coals with different coal ranks were characterized and their effects on the properties of coal water slurry (CWS) were investigated. The results indicated that high content of vitrinite and low content of inertinite in coal with similar ash content are beneficial to the slurryability, static stability and rheological behavior of CWS. From the results of plurality fit linear, both vitrinite and inertinite showed the remarkable effects on the properties of CWS, while the exinite had less effect. The inertinite content in coal shows significant effects on the static stability of CWS. The soft sediment is normally formed after 15 days when inertinite content in coal is lower then 30%. Fit exponential analysis indicated that the maximum reflectivity of vitrinite had a good correlation with the slurryability of CWS, the slurryability increases with increasing maximum reflectivity, which can be used as a parameter to estimate the slurryability of CWS.