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The Mediterranean basin, as a crossroad of air masses from different origin, is affected by aerosol of different size, composition and properties, including desert dust transported from Africa. Aerosol remote sensing techniques provide a great opportunity for the observation and the understanding of the aerosols behavior since they allow systematic and extended spatial and temporal sampling of the atmosphere. Cloud Condensation Nuclei (CCN) are aerosol particles which provide surface area for water condensation, enhancing formation of cloud droplets. Cloud Condensation Nuclei Level-3 daily product from Moderate Resolution Imaging Spectroradiometer (MODIS), sorted into 1 by 1 degree grids, has been acquired from MODIS website (modis.gsfc.nasa.gov) in order to investigate the impact of dust transport to CCN formation over the Mediterranean. The number of CCN in the atmospheric column, as retrieved at the spectral band of 550 nm during major dust events, indicate that mineral dust episodes lead to higher values of CCN (up to 10 times higher) than observed under background conditions. The derived CCN column concentrations over the Mediterranean for a reference day vary between 2x10(8) and 5x10(8) cm(-2), whereas, during dust cases, the values typically range between 3x10(8) and 2x10(9) cm(-2).