As separation techniques, pervaporation occupies a special place in the chemical industry. It is the only membrane process primarily used to purify the chemicals. Pervaporation, in its simplest form, is an energy efficient combination of membrane permeation and evaporation. Separation of the alcohol-water mixture by hybrid distillation pervaporation has received increasing attention in industry. Normally Conventionally azeotropic distillation is used to remove the water from an azeotropic ethanol/water mixture. The aim of this paper is to show the comparative study of pervaporation over a conventional azeotropic distillation for the separation of ethanol water mixture. It shows how pervaporation is better option over a conventional method due to its various factors like lower operating costs resulted from lower energy consumption, reduced waste water treatment and the absence of a chemical entrainer, reduction in capital cost and operating cost. All this aspects are pushing the development and adoption of new better technology over a conventional one. Despite the fact for the adoption of new technology like pervaporation, chemical engineers will need all of their skills to select the very best application and maximize the benefits to their plant.