A series of conversion-absorption ZnO based desulfurizers were prepared by using industrial ZnO and ZnO obtained by basic zinc carbonate decomposition as active component respectively, γ-Al2O3 as structure additive and K2CO3 as basic additive. The effects of ZnO precursors and γ-Al2O3 precursors on the desulfuration properties of prepared ZnO based desulfurizers were investigated at 300℃and atmospheric pressure with a gas space velocity of 2000 h-1. The results showed that the pore structure and basicity of ZnO based desulfurizers could significantly affect their desulfurization properties. The desulfurizer using ZnO obtained by basic zinc carbonate decomposition as the active component had high removal efficiency and good breakthrough sulfur capacity, and the breakthrough sulfur capacity was increases about 10 times comparing with that of the desulfurizer using industrial ZnO as the active component. In addition, the γ-Al2O3 prepared by different precursors had influences on the desulfurization properties of the prepared ZnO based desulfurizers. The γ-Al2O3 decomposed from pseudo boehmite obviously improved desulfurization properties of the desulfurizers, the breakthrough sulfur capacity was 12.18%. Among these desulfurizers, the desulfurizer using ZnO decomposed from basic zinc carbonate as the active component, γ-Al2O3 decomposed from pseudo boehmite as the structure additive and K2CO3 as the alkaline additive, could convert and absorb COS with a COS conversion of 99.98% and a breakthrough sulfur capacity of 4.03%.