The effects of the type and the amount of various catalysts on the rate of the carbothermic reduction of zinc sulfide in the presence of calcium oxide were studied using thermogravimetric analysis system (TGA). Experimental results revealed that the order of the effects of the catalysts is Li2CO3 approximate to Na2CO3 Na2SO4 > Li2SO4 > K2CO3 > K2SO4. It was also observed that with more Li2CO3 the reaction is faster, when the amount of Li2CO3 was less than 2.0 wt.%. (c) 2007 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.