Optical properties of aerosols associated with haze events over Seoul were examined using ground-based skyradiometer and satellite-borne CALIOP and MODIS measurements over the 2009 similar to 2010 period. It is shown that aerosol optical thickness (AOT), Angstrom exponents (alpha), and fine-mode particles increase during the haze events. The CALIOP-measured vertical profiles of aerosol during the haze events revealed that most of aerosols are loaded within layers below 4 km altitude. A large portion of these events appear to be related to the long-range transport of aerosols from China; about 35% and 18% of the haze events observed over Seoul were traced back to northern China and southern China, respectively. Compared with optical properties for locally-induced haze events (25%), these long-range transported aerosols are found to have relatively higher AOTs.