It is expected that visible/infrared and microwave remote sensings provide independent information from a target of interest. We have conducted simultaneous visible/infrared and Synthetic Aperture Radar(SAR)observations of a coastal lagoon area, specifically Lakes Shinji and Nakaumi. On September 21, 2000, simultaneous measurements by SPOT/HRV(visible and near-infrared)and ERS-2/AMI(SAR)were conducted. Turbidity distribution is obtained from the SPOT/HRV, and combined with streak-like SAR signatures. Borderline of lake water flow is then clearly identified from the two images. On August 23, 2003, simultaneous measurements by TERRA/ASTER(visible and near-infrared)and Pi-SAR (airborne SAR)were conducted. It is shown that the turbidity distribution from the ASTER and Pi-SAR images appear to correlate with the strong westery wind field. It is also suggested from the Pi-SAR image that surface wind near the coast line is weaker than the center of the lakes.