Mercury, bounded in soil, comes in considerable grade from industrial sources, among which the firing processes of different kinds of conventional fuels predominate. The paper presents the results of investigations soils contamination by mercury in surroundings of conventional coal-based power station. The investigation covered the area around the one of the oldest Polish power stations "Siersza ". For many years this power station was using poor-quality coals from neighbouring coal mine "Siersza ". As a result of research it was found that the increased concentration of mercury appears in soil samples taken from the places laying on directions compatible with local directions of the winds, and at least 2-3 km distant from emitters. In the immediate proximity of the power station's emitters, the mercury pollution was small. General pollution level of examined soils by mercury does not exceed the admissible values. The research proved that around that power station the contamination by mercury was noticeable, however the mercury content in soil exceeding the permissible standards was not observed. The results of investigations do not confirm therefore some literature suggestion about considerable contamination by mercury resulting from flue gas emissions from coal-based power stations.