Synthetic Aperture Radar (SAR) is a high resolution microwave active imaging sensor with all-weather, day or night time observation capability. SAR has an information aquisition capability that differs from that obtained by optical sensors. Because a very large number of operations are required in SAR data processing, the authors have applied a non-von Neumann type high speed computer (data-flow computer) called NEDIPS to SAR data processing, and have realized one of the highest speed SAR data processing systems. In this paper, the characteristics of SAR data processing and an outline of the SAR data processing system using NEDIPS are introduced. Finally, the high speed SAR data processing techniques used in the system are discussed.