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.