This study is intended to the diagnostic accuracy and reproducibility rate according to the input devices and the video signals, potential technical problems of the telepathology system and possible physical and psychological impacts. Web based in telepathology system had been developed and in use, but their functional capability and diagnostic accuracy are considered to be inferior to those of conventional optical microscope. We devised a telepathology system using our existing microscope equipped with CCD camera unit that has no restriction of network speed. Total 55 histopathologic cases from various organs were selected. Three pathologists are involved in making diagnoses. The resulting diagnostic accuracies were 1CCD camera with composite video signal was 86.2%, 3CCD camera with composite video signal was 93.1% and 3CCD camera with component video signal was 95.0%. The 3CCD camera with component video signal resulted 95.0% diagnostic accuracy and was superior to 1CCD and 3CCD camera with composite video signal. At this time of problems were not noted in the monitor quality.