It is analysed the efficiency of the Korean IT industry using CCR and BCC models of the DEA(Data Envelopment Analysis) method in this study. In this study, the Korean IT industry is classified into 7 groups which are Displays, Digital Contents, Wireless Communication Devices, Telecommunication Services, Semi-Conducts, Broadcasting Services and Computer Services that the efficiency of each groups is analysed contrastively. And it is considered to find a way to improve the efficiency of inefficient companies using the slack variable analysis. Also the Super DEA is used to find the relative rank among companies that their efficiency is 100% and the change of the Korean IT efficiency is measured by the Time Series Analysis from 2005 to 2007 for 3years as well.