In underground coal mines, grouting method is employed in order to reinforce the floor and to control the movement of groundwater into the roadway. The effectiveness of floor reinforcement with grouting is already understood. However, the seepage behavior of the grouting material into the floor is not clearly understood. Therefore, grouting is today normally based on empirical relationships and on the experience of the grouting personnel. To assist grouting projects, it must be acknowledged that many of the flow processes occurring during grouting so far defy mathematically analysis. From this point of view, this paper discusses the behavior of grouting material, when it is injected into the roadway floor, by means of 3-D Eulerian-Lagragian seepage analysis.