[Objective]The research aimed to study petroleum distribution in water area of Jiaozhou Bay. [Method]According to investigation data in water area of Jiaozhou Bay in June,July,September and October of 1980,the content,distribution characteristics and reason of petroleum in surface and bottom water body of Jiaozhou Bay were analyzed. [Result]Petroleum pollution in water area of Jiaozou Bay was serious. Petroleum hydrocarbon concentration in surface water body of Jiaozhou Bay in June,July,September and October was during 0. 0120. 155 mg /L,showing that petroleum hydrocarbon concentration in surface water body of Jiaozhou Bay reached national class-two seawater quality standard. The isoline of petroleum hydrocarbon concentration in surface water body in July and September formed a series of parallel lines at different gradients. Petroleum hydrocarbon concentration in surface water body gradually decreased from northeast shore to southwest bay mouth,and isoline mainly concentrated near the mouths flowing into sea of Loushan River,Licun River and Haibo River. [Conclusion]The research could provide basic data for marine environmental management and scientific decision-making in the sea area. [Objective] The research aimed to study petroleum distribution in water area of ​​Jiaozhou Bay. [Method] According to investigation data in water area of ​​Jiaozhou Bay in June, July, September and October of 1980, the content, distribution characteristics and reason of petroleum [Result] Petroleum pollution in water area of ​​Jiaozou Bay was serious. Petroleum hydrocarbon concentration in surface water body of Jiaozhou Bay in June, July, September and October was during 0. 0120. 155 mg / L, showing that petroleum hydrocarbon concentration in surface water body of Jiaozhou Bay reached national class-two seawater quality standard. The isoline of petroleum hydrocarbon concentration in surface water body in July and September formed a series of parallel lines at different gradients. Petroleum hydrocarbon concentration in surface water body gradually decreased from northeast shore to southwest bay mouth, and isoline mainly concentrated near the mouths flowing into the sea of ​​Loushan River, Licun River and Haibo River. [Conclusion] The research could provide basic data for marine environmental management and scientific decision-making in the sea area.