Brown coal was dewatered under hydrothermal dewatering (HTD) conditions. The variation in moisture content and distribution of brown coal were studied. The results showed that equilibrium moisture content decreased from 28.2% to 9.6% after hydrothermally treated at 300 degrees C. Three types of moisture existed in brown coal and its HTD products according to the coal-water binding energy (E-b): Surface adsorption water (E-b < 2000 kJ/kg), interparticle water (2000 < E-b < 9000 kJ/kg), and interior adsorption water (E-b > 9000 kJ/kg). Drying rates of these types of moisture respectively followed logarithmic, linear, and indicial equations.