Korea government relaxed the regulation of Electronic Finance Supervision(hereafter, EFS) in January, 2019 before global IT companies have established a Data Center for private financial information. The deregulation made the Microsoft and the Google build in 2019 and provide the Cloud Service in 2020, and also many global IT companies, like Apple, Oracle, Facebook, declared that the Data Center would construct in Korea. We estimate the environmental cost from a Data Center under an assumption that the electric power facility capacity of a Data Center is 40, then it cost about 6.4 billion Korean Won, and converted it to the present value, 87 billion Korean Won, by using both the life cycle period(20 year) of a Data Center and the social discount rate(4.5%). It implies that Data Center has a negative influence on the environment. Nevertheless, the EFS deregulation does not provide any kinds of restrictions or conditions on the environment now. In fact, overseas global IT companies are well aware of the environmental problems induced by their Data Centers and steadily make efforts to use the renewable energy more, but they don’t still take the same action in Korea. In this context, we derive a following policy implication: any kinds of supplementary and environmental condition for overseas global IT companies to deploy and build the Data Center in Korea should be added, i.e., the production of the electricity with a renewable energy by themselves, etc.