There Polycyclic aromatic hydrocarbons (PAH : Benzo (a) Pyrene (BaP), Benzo (k) Fluoranthene (BkF), Benzo (b) Fluoranthene (BbF)) in 23 surface sediments and 2 core sediments from The Sea of Suo have been analyzed by HPLC with fluorescence detection. BaP concentrations in the surface sediments ranges from 10.4 to 338 ng · g<SUP>-1</SUP>-dry sediment. PAH concentrations in the eastern area of the sea are lower than these in the central and western area of the sea. <BR>The increase in PAH toward the surface from 45cm depth at St. 23 and from 30cm depth at St. 1 were approximately exponential and PAH concentrations under those depth were constant. The age of 45cm depth at St. 23 corresponds to about 1920 by <SUP>210</SUP>Pb-chronology. <BR>Distance indices were calculated to examine the similarity among samples in terms of the relative abundance of individual PAH. Samples except for St. 15 were classified into 2 groups (Group I, II and Group III, IV) by distance indices. <BR>These results suggested that the PAH input in areas of GroupI, II and III, IV were different.