The present disclosure relates to a coal drying system for removing water contained in coal used as a fuel of a thermoelectric power plant with superheated steam. The system prevents the incomplete combustion of the coal by removing water existing inside and outside the coal fuel of the thermoelectric power plane, thereby improving a heating value of coal and minimizing the discharge of pollutants, prevents the corrosion of the system and improves the durability, and increases the use of low-quality coal of which the demand is low, thereby improving the stable supply of the coal.