Features of distrilbution of transmission and their relation to front, tidal current and circulation in the Southern Yellow Sea in late autumn, 1983 are described. It has been found from observations that the distribution of transmission is very different on the two sides of the front of the Cold Water Mass of Yellow Sea, and that the transmission is higher in the upper layer in the Gold Water Mass area and lower in the bottom layer where isoplethes appear to be horizontal and related to quasimaximum tidal current. In contrast，transmission outside the front of Cold Water Mass is also lower and homogeneous vertically. The Water in the area where tidal mixing is strong is more turbid. It seems that diffusion of suspended matter is restrained by thermocline. Main currents such as the Warm Current and Coastal Current of Yellow Sea，and northward residual of the Taiwan Warm Current etc.can be easily identified from transmission distribution.