The transmission system from analyzed data of EPMA (JEOL JXA-733 and JXA-8600) to a personal computer through RS-232C communication line was developed. File format is also converted by this system for some spread sheet programs, such as Lotus 1-2-3 and Microsoft Excel. It is required to make only a few cables for the system. Such a communication method and the convert algorithm using BASIC program may be applicable to various kinds of analyses machines.