Abstract: Based on the fundamental data of kinetics, the one dimensional mathemtical mode l for the three phase slurry reactor of 30 000t/a dimethyl ether in the typical i ndustrial instance has been established by taking hydrogenation of CO,CO 2 and dehydration of methanol as independent reaction, and CO and CO 2 as key compone nts. The design parameter of the reactor about technology and equipment has been obtained. The influence of operating condition on catalyst particle concentrati on on axial distribution, reactor height and dimethyl ether reaction result has been discussed.