This paper deals with the role of the Seasat SAR

SIR-A and SIR-B in earth science research

which have acquired the spaceborne radar images of the earth surface uniquely. The activities of the active microwave remote sensing in the coming ten years have been described

especially the ALMAZ SAR

ERS-1 SAR

JERS-1 SAR

SIR-C

Radarsat SAR and EOS SAR systems. It is prospected that the 1990’s will be the key decade for technical development and geoscience application of the spaceborne radar remote sensing.