eXtreme Programming (XP) is an agile software development process in which both short period iterative development and communication between project members are important. Software development aims at producing high quality programs within a promised period. To gain an improvement in product quality, XP proposes twelve practices such as Pair Programming, Test Driven Development, Refactoring, etc. Pair Programming makes it possible for all project members to deepen understanding of their programs, and also it becomes easy to find the error of them. Consequently, it improves quality of their programs. It will be required that the pair has to work together with sufficient communication. However, in realistic software development, it is necessary to carry out development in the distributed environment by time and spatial restrictions of developers, such as office environment, and telecommuting, an international project. In XP, since communication is important, we propose XP support environment on a network from the viewpoint of pair programming support so that the quality of a program can be improved also in distributed environment.