Ethylene oxide(EO)is a sold-out intermediate material for producing various chemicals.Major chemical companies are interested in whether new EO plant can create profit.This research is undertaken to investigate the economic feasibility of EO production.Direct oxidation of ethylene using silver on alpha-Al2O3 catalyst type is adapted to produce EO of 60 000t year.We conduct the conceptual design.Firstly,we synthesize the optimal structure and then determine optimal conditions and the size of the equipments.Feasibility study shows that profit and loss turning point turns out to be 3.2 years based on the present market price.In addition,we conducts the economic analysis to prepare the risk of raw material market price variation ranging from 70% to 130%. Major chemical companies are interested in whether new EO plant can create profit. This research is undertaken to investigate the economic feasibility of EO production. Direct oxidation of ethylene using silver on alpha-Al2O3 catalyst type is adapted to produce EO of 60 000t year. We conduct the conceptual design. Firstly, we synthesize the optimal structure and then determine optimal conditions and the size of the equipments.Feasibility study shows that profit and loss turning point turns out to be 3.2 years based on the present market price.In addition, we conducts the economic analysis to prepare the risk of raw material market price variation ranging from 70% to 130%.