Abstract: Petroleum hydrocarbons has biological cumulative． It can be retained in the environment for a long time． If the behavior and the end-result of the petroleum hydrocarbons in the environment can be mastered，it has the great significance to control the pollution of petroleum hydrocarbons and protect human's health． Biodegradation is the main process to the fate of petroleum hydrocarbons in soils-groundwater system． The focus of this review is on the migration of petroleum hydrocarbons in the soil-groundwater system，the microorganisms degrading petroleum hydrocarbons，biodegradation mechanisms and the methods which are used to remedy petroleum hydrocarbons-contaminated soils and groundwater，and use of microbial molecular ecology to monitor the process of the biodegradation，and point out the future directions．