In this paper, Knowledge Flow Diagram(KFD) is proposed as a new modeling tool for the enhancement of intra-organizational knowledge sharing. KFD shows what knowledge is transferred from one process to another process with the three constructs of knowledge, flow, and process. KFD can be revised in the aspects of effectiveness and efficiency. In the aspect of effectiveness, we can improve the effectiveness of the knowledge flow using the media richness theory. And in the aspect of efficiency, we can improve the efficiency of the knowledge flow by considering the cost of the flow. Based on these principles of improvement, the method of enhancement of intra-organizational knowledge sharing is proposed. And by applying this method to the real case of a CA-TV home-shopping company, we found the opportunities of the improvement of the knowledge sharing in the company and made improvement plan for it. This method couldn't solve all the problems of knowledge sharing, but it was useful.