The optical data which collected in situ in inshore and offshore of Daya Bay in July 26, 2 010 is presented. The data is collected by using the instrument, which synchronously measured the volume scattering function in seven directions from 20o to 160o, the attenuation coefficient, and the depth of water. The analysis of the data indicates that in Daya Bay, in general, the scattering and attenuation increase with depths after 4 m below the surface, while it decreases with depths from near surface layer to 4 m. But not for the area near Daya Bay Nuclear Power Station due to the unique geographical environment of it.