An eco-friendly additive isolated from a natural plant has been developed in the laboratory for preparation of coal water slurry (CWS) of some specific Indian coal. The effect of additive concentration, the rheological behavior of CWS at weight concentrations varying from 55-63.7% using a rotational viscometer, the static stability tests, etc., have been investigated. The nature of the slurries followed Bingham plastic behavior in these range of concentrations, and the slurry viscosity recorded over these solid weight concentrations varied between 0.42-0.97 PaS by using the natural additive. The rheological behavior of CWS was compared with commercial additives with a possibility to replace it with the natural additive. The static stability studies on CWS of the low- and medium-ash coal water slurries were found to be 27 and 21 days, respectively.