A flat organization is a firm that has an organizational structure with few or no levels of middle management between employee and executives. The idea is to take advantage of well-trained workers when they are more directly involved in the decision making process, rather than closely supervised by various layers of management. This paper presents an empirical investigation to determine critical success factors on building information technology (IT) based flat organization in a case study of banking industry. Using principal component analysis, the study applies factor analysis for two internal and external factors. In terms of internal factors, there are three factors including Processes and the electronic decision making, Teaching and Electronic Learning and Work in IT. In addition, the study has detected four factors including Electronic Supply, IT structure, Appropriate IT usage and Electronic Communication.