Abstract: This packing is a new, high efficiency and regular packing. The use of two layers of stainless steel gauze gives good wettability and uniform liquid distribution over the entire packing surface, so that the separation efficiency is increased sensibly even with liquids of high surface tension like water and under low liquid load. Vacuum rectification tests on D2O/H2O system have been performed with a column of 10cm inside diameter, the packing hight of 200cm, and column top pressure about 125 torr. By the use of the measured data, satifactory correlations for pressure drop and mass transfer of this packing were obtained in the article.