Char conversion is the rate-determining step for coal gasification in supercritical water, because the main components of char are polycyclic aromatic hydrocarbons (PAHs) with chemical stability. Anthracene was selected as the model PAR compound to explore the gasification mechanism of coal in supercritical water. The experimental parameters investigated with autoclaves were within the following ranges: temperature, 600-750 degrees C; residence time, 5-30 min; and pressure, 23-25 MPa. The main gas products were H-2 and CO2. The liquid intermediates were analyzed by gas chromatography mass-selective detection (GC-MSD) for qualitative analysis and quantitative analysis, respectively. Benzene and naphthalene were found to be relatively stable compounds in the liquid products. Effective catalyst and appropriate temperature were obtained to enhance the gasification process.