Abstract: The test system includes a biomass pyrolysis reactor with rich husk as feedstock and a tar cracking reactor with dolomite as catalyst. The effects of pyrolysis temperature on the tar yield, cracking temperature and residence time on the tar conversion rate are examined. The results show that tar conversion rate increases with increasing cracking temperature and residence time. The tar conversion rate during catalytic cracking is higher than that during thermal cracking at the same temperature. The tar catalytic cracking mechanisms are analyzed by comparison of thermal and catalytic cracking results. The gas components after catalytic cracking are investigated. It shows that H2 and CH4 increase while CO2, C2H6, and C2H2＋C2H4 decrease due to the water-gas shift reaction. The results indicate that catalytic cracking of tar with dolomite is suitable for tar elimination.