Petroleum hydrocarbons have become one of the most important pollutants in the sea due to oil pollution accidents. Large quantities of petroleum hydrocarbons would cause serious harm to aquatic animals. Effective determination methods can monitor the content of petroleum hydrocarbons in aquatic animals, and timely carry out corresponding solution for oil pollution accidents. In this paper, the petroleum hydrocarbons composition, their harm to aquatic animals, and their determination methods were summarized in order to provide references for relative studies.