Abstract: In this paper, the numerical simulation is carried out to study the effect of the number of the holes, the size of the droplets and the velocity on the separation efficiency and the pressure drop in the tube mist eliminator. The turbulence model and the discrete phase model are used respectively to calculate the movements of the continuous phase and the droplets. The results show that the separation efficiency of the eliminator increases with the increase of the droplet diameter and the velocity. In particular, the eliminator is more effective in removing small droplets. There are approximately 62% of 5 μm and 69% of 10 μm droplets being captured by the tube mist eliminator. In addition, the fins with holes can reduce the pressure drop by 50% in the tube mist eliminator under the studied condition. This study concludes that the tube mist eliminator possesses high separation efficiency on small droplets. Cutting holes on the fins can lower not only the flow resistance, but also the separation efficiency. This conclusion can provide a good basis for theoretical researches and industrial application of the tube mist eliminator.