The effect of coal char on the decomposition of rice straw derived tar was investigated in a two-stage fixed bed reactor. The reactor was divided into a pyrolysis zone (upper part) and a volatile-char contacting zone (lower part). Rice straw was pyrolysed at different temperatures in the upper part. Coal char, prepared by the pyrolysis of Indonesian coal at either 600°C (char600) or 800°C (char800), was located in the lower part. Volatiles from the rice straw (upper part) were produced and then came in contact with the coal char at the lower part under the N 2 (pyrolysis) or steam/N 2 (steam reforming) gas flow. Under pyrolysis, both char600 and char800 exhibited a catalytic effect on the thermal tar decomposition. The coal chars also played a significant catalytic activity on the decomposition of the heavy aromatic hydrocarbons that were generated at a high pyrolysis temperature. In the presence of steam, char600 also exhibited a catalytic role in tar steam reforming, while char800 did not reveal any such significant catalytic activity because of the predominant coke/carbon formation.