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The seasonal evolution of the aerosol vertical distribution in the Central Mediterranean is studied using measurements made in the period 1999-2008 at Lampedusa with an aerosol Lidar and a multi filter rotating shadowband radiometer (MFRSR). Measurements show that the aerosol vertical distribution is largely influenced by Saharan dust, which produces a strong annual cycle both in aerosol vertical extension and optical depth. Dust layers are present in the profile in 38% of the cases throughout the year, and in 57% in summer. The dust top altitude peaks in late spring, up to 9 km. The monthly average optical depth at 500 nm for dust cases shows a main peak in July (0.38), and values exceeding 0.2 throughout March-September. Conversely, non-dust cases show a very limited seasonality, both in vertical distribution and aerosol optical depth. The monthly average optical depth for non-dust cases is smaller than 0.17 throughout the year. During winter, the vertical distribution and optical depth are very similar for both dust and non-dust cases. The seasonal average extinction coefficient profiles for dust and non-dust cases show remarkable differences in spring and summer, when values of the extinction coefficient exceed 0.5 x 10(-4) m(-1) throughout the altitude range 0-4.5 km for dust cases, and 0-1 km altitude for non-dust cases, respectively. Estimates of the Lidar Ratio are derived by combining Lidar and MFRSR measurements. The average Lidar Ratio at 532 nm is about 30 sr.