The catalyst pore structure parameters have a great influence on theintraparticle diffusion which mainly determines the global reaction rates.In thispaper,the effects of pelleting pressures on the global reaction rates were studiedby the chemical reaction engineering theory.As a research system the Cu-basedmethanol synthesis catalysts with different pore structure parameters(specificsurface,pore volume,pore radius distribution,porosity,particle density,tor-tuosity factor etc.)have been prepared by changing the catalyst pelleting pres-sures.Based on the parallel intrinsic reaction rate equations of CO and CO_2 hy-drogenation on C301 Cu-based methanol synthesis catalyst and on the assump-tion that the intrinsic reaction rate constants per unit internal surface are thesame,the diffusion-reaction equations and parallel path cross-linked pore modelwere used for modeling the behavior of the catalyst pellet under industrial con-ditions.The models of global reaction rates had been established for CO andCO_2 hyd The catalyst pore structure parameters have a great influence on theintraparticle diffusion which primarily determines the global reaction rates.In this paper, the effects of pelleting pressures on the global reaction rates were studied by the chemical reaction engineering theory. As a research system the Cu-basedmethanol synthesis catalysts with different pore structure parameters (specificsurface, pore volume, pore radius distribution, porosity, particle density, tor-tuosity factor etc.) have been prepared by changing the catalyst pelleting pres- sures. Based on the parallel intrinsic reaction rate equations of CO and CO_2 hy-drogenation on C301 Cu-based methanol synthesis catalyst and on the assump-tion that the intrinsic reaction rate constants per unit internal surface are the same, the diffusion-reaction equations and parallel path cross-linked pore model used for modeling the behavior of the catalyst pellet under industrial con dition. The models of global reaction rates had been established for CO andCO_2 hyd