Ionic compositions of water soluble aerosols observed at the seashore of the Tong-gu Bay in Taishan,Guangdong Province during Feb. 1989,namely,Cl^-,NO^_₃,SO⁼₄,Na⁺,K⁺ and Mg⁺⁺ ,are analyzed. It is found that the dominant ions are Cl^- and Na⁺ ,which are of marine salt aerosol. The same origin is with Mg⁺⁺,too. K⁺ mainly comes from the continent. And SO⁼₄ from sea salt mostly. It does reveal,however,the large scale high pollution of sulfar in the continent of East A-sia. The study points out that high concentration of SO^-₃ is of 100% non-sea-salt origin. It is obvious that this is related with local farming and household cooking.