An effect of the high-power electromagnetic pulses onto the droplet of coal-water slurry inside the furnace was investigated. In contrary to the previously investigated laser-induced fuel atomization that occurs at the room temperature, the pre-heated (to 400 K) slurry becomes dry enough to prevent the explosion-like steam forma-tion. Thus, fuel does not atomize and the ignition does not accelerate. Furthermore, the absorption of several laser pulses leads to evident sintering of irradiated surface with following increase of the ignition delay time for up to 24％. Variation of the pulse energy in range 48-118 mJ (corresponding intensity up to 2.4 J·cm-2) leads to certain variation of the increase of ignition delay. The strong pulsed overheating of the coal water slurry which does not initiate the fine atomization of the fuel generally makes its ignition longer.