This paper presents a comparison between simultaneous radiance measurements and aerosol retrievals of POLDER 2/ADEOS 2 and MODIS/Terra, two instruments devoted to monitor the Earth and its atmosphere from space. This study focuses on aerosol remote sensing over ocean. Geophysical results from both inversions are compared. MODIS and POLDER total radiance (and also polarized radiance for POLDER) measurements are compared with radiance simulations based on POLDER and MODIS inversed aerosol products (cross-simulations). Such comparisons emphasize advantages of each instrument and its inversion process. Both instruments generally agree on aerosol retrievals except when POLDER detects nonspherical particles within the coarse mode, which is not possible for MODIS. Combining measurements provided by POLDER 2 and MODIS, the spectral variation of optical properties of nonspherical aerosols can be derived. In order to retrieve more accurately aerosol optical properties, combining directional and polarized information from POLDER 2 with simultaneous MODIS spectral data is needed. The results of this study will guide us in the realization of a coupled inversion scheme.