The feasibility of using natural limonite ore for catalytic cracking of biomass pyrolysis volatiles was investigated to study the effects of the catalyst-treated method, temperature, space velocity, and atmosphere on carbon conversion and gas yields. Limonite ore has a certain catalytic activity in the cracking of tarry material, and the activity could be significantly enhanced after reduction with H-2. When reduced limonite was used, the gas yield increased to the maximum value of 41.6 mmol/g and the yield of carbon in water-soluble tar decreased to a negligible value (0.7%) by increasing the reforming temperature from 400 to 650 degrees C. The reforming activity of reduced limonite is comparable to the commercial Ni/Al2O3 catalyst. Steam can inhibit carbon deposition on limonite and give a H-2-rich gas (H-2 content of 70.4 vol %) in a high yield of 74.1 mmol/g at 700 degrees C. A lower space velocity improves carbon conversion and gas production. The study revealed the possibility of using limonite as an alternative and attractive catalyst to the commercial precious metal catalysts for catalytic gasification of biomass in low temperatures.