Physical and optical parameters within the atmosphere-ocean system have been retrieved by a multiple scattering analysis of the reflectance and degree of linear polarization data measured by the airborne POLDER sensor in Medimar campaign in 1991. Assuming an atmosphere-ocean system with a Cox-Munk type rough sea surface model, the theoretical reflectance and -degree of linear polarization were computed by the doubling and adding method for several different models. In this study the retrieval was made by assuming a fixed refractive index of the aerosol particles, i.e., Nr=1.33-0.0i. We obtained several important results in this study as follows: 1) By comparing computed results with the observed data at 0.85m, we rejected the oceanic type aerosol model and found Junge type aerosol model with its index range of 4.0v4.5 as an appropriate model for aerosols at the observation time. 2) The reflectance data analysis in the perpendicular plane rejected an isotropic Cox-Munk model, but it indicated that an anisotropic Cox-Munk model should be used in the sea surface wind field retrieval. 3) The surface wind speed was estimated to be 10.0m/secV15.0m/sec with an best estimate of V=12.5m/sec, which agrees with the observed wind speed of V=14.4m/sec. The range of the water column reflectance was also estimated to be 0.025rwc0.045 from Medimar reflectance data at 0.45m. 4) Further study should be made for other refractive indices of the aerosol particles. More refinement of the present multiple scattering code to include upwelling polarization components from below the sea surface is also necessary.