For retrieving sea surface wind speed, good results were achived with CALIPSO lidar night data. During daytime, spaceborne lidar has a poor signal to noise ratio due to the irradiation of direct sunlight and the sky. Based on the existing retrieval model, sea surface wind speeds of day and night were retrieved using CALIPSO lidar 532 nm day and night single-shot data of January, April, July and October in 2007, with aerosol optical depth (AOD) for two-way atmospheric transmittance correction. The collocated version 7 AMSR-E sea surface wind speeds were used as the true values for comparison. The results show that, it is feasible to use CALIPSO daytime lidar data for sea surface wind speed retrieval, and the precision can be increased with the use of appropriate retrieval model.