Nowadays the customer is classified with external customers and the inside customers. Which are not only end users who consume products but also all people who contribute to their earnings through the management activity of the enterprise. Furthermore, the fact that the external customer satisfaction index and inside customer satisfaction index are closely related is supported by many researches. It is interpreted if the inside customer satisfaction is not improved, achievement of the external customer satisfaction cannot be easy. In this paper, First, we will deduce the inefficient index through DEA model in each department after setting up the weight of items of inside customer satisfaction and measuring them. Second, as well as research entire models about improvement methods of inside customer satisfaction getting improvement methods for reaching a goal in the minimum amount of efforts.