This work considers the methodology of hydrogeological forecasts of the conditions of flooding of coal mines. Relevance of the topic is determined by the mass flooding of mines in the main coal mining areas, which raises serious problems associated with the provision of environmental and industrial safety of the liquidation work. At flooding of mines the developing hydrodynamic processes have certain specificity, therefore a necessity of additional analysis and perfection of existing numerical geofiltration models has arisen. Some methodological methods used in forecasting of mine flooding conditions are stated.