Abstract: Distillation experiment of dimethyl ether(DME) is carried out in a tower with wire-coiled rectangle helix ring packing, the feeding liquid is fed into the middle of the packing layer, and the effects of process parameters on the distillation of DME were investigated under the pressure of 0.55MPa~0.95MPa, the feed temperature of 20℃~80℃, reflux ratio of 0.1~0.6 and DME mole fraction in feed from 0.070516 to 0.135357. The results showed that the concentration of DME increases with the increment of reflux ratio and DME mole fraction in feed, and the concentration of DME decrease with the increment of the operation pressure. It is advisable that feed temperature should be limited to not more than 70℃. A mathematical model was established to research the distillation process on the basis of equilibrium stage theory. The cyclical nested-iteration method in sequential convergence was developed to solve the model equation. The results showed that the simulation values from the model are in good agreement with the experimental date.