Among the new coal technologies the burning of low-grade coal in the form of coal-water slurry fuel (CWSF) is of a great interest. The basis of CWSF is a highly concentrated coal-water slurry consisting of finely ground coal, water or other liquid and plasticizing agents. The development of CWSF technology is highly relevant for solving global problems of resource conservation and ecology. The study is dedicated to CWSF properties with respect to Kansk-Achinsk coal and water. This paper presents the results of the influence of CWSF’s preliminary cavitation water treatment on the combustion dynamics of fuel, (including the features of the combustion temperature trends, delayed ignition time and time of complete combustion) and on its environmental characteristics. A rotary-type hydrodynamic oscillator at high angular velocity (10000 rpm) was used in supercavitation mode. It is shown that the technology of cavitation water treatment leads to a change in the dynamics of CWSF’s combustion and to an additional decrease in NOx emissions by 1.6 times, CO2 by 1.3 times.