This paper introduces the effect of dolomite and limestone on waste tyre pyrolysis When waste tyre was pyrolyzed in 700?℃, the derived gases was passed through the catalyst zone in which the temperature was controlled at 700?℃, 800?℃and 900?℃, respectively It is found that both dolomite and limestone affect the product distribution of tyre pyrolysis with erhancing gas yield and effective absorption of H 2S The effect of these catalysts on tar cracking is obvious at 900?℃, however, the life of catalyst is short The product yields are about 40% for gas, 30% for liquid and 30% for char in the presence of dolomite and limestone The result indicates that multi use of the pyrolysed product is highly recommended [WT5H1]