With the continuous acceleration of social modernization,a large number of volatile organic compounds (VOCs) are discharged into the atmosphere in industrial production and daily life,which seriously harms the ecological environment and human health. Therefore,the emission control and degradation of VOCs have attracted wide attention. In recent years,due to the advantages of low cost,high purification efficiency,simple operation and free secondary pollution,biodegradation of VOCs has been extensively studied and applied. However,because of the low mass transfer of hydrophobic VOCs from gas phase to liquid phase,the degradation efficiency of VOCs in bioreactor is low. The influencing factors of biodegradation of hydrophobic VOCs were analyzed from the aspects of mass transfer efficiency,microbial community types and packing performance. The methods to improve the biodegradation efficiency of hydrophobic VOCs,such as the application of fungi,the addition of surfactants,the utilization of hydrophilic compounds and new biodegradation technologies,were discussed,and the research direction of biodegradation of hydrophobic VOCs in the future was prospected. It is particularly important to improve the mass transfer efficiency of pollutants in bioreactors. In the future,researches on migration and degradation mechanism of hydrophobic VOCs in biofilms should be strengthened. The degradation efficiency of VOCs by the inoculated bacteria decreases with environmental changes,such as decreasing moisture and pH. The packing in the bioreactor can affect the attachment of microorganisms and the formation of biofilm,which directly affects the degradation efficiency of VOCs. The selection and development of suitable packing can provide a good ecological environment for the growth,metabolism and biofilm development of the microbial community,and provide guarantee for the long-term stable operation of the reactor. The advantage of aerial mycelia could help fungi to absorb hydrophobic VOCs which can improve the degradation efficiency of VOCs,so as to improve the removal rate of hydrophobic VOCs. However,few fungi that can degrade hydrophobic VOCs have been found so far,more fungi that can degrade hydrophobic organic compounds should be developed in the future. Surfactants can increase their solubility by partitioning hydrophobic organic pollutants into the hydrophobic core of surfactant micelles and improve the mass transfer efficiency of hydrophobic VOCs. Compared with traditional chemical surfactants,biosurfactants are natural compounds that are more environmentally friendly,less toxic,and more easily biodegradable. Future research should pay more attention to biosurfactants. Mixing hydrophilic compounds with hydrophobic VOCs can interact with different pollutants,which improves the solubility and bioavailability of hydrophobic VOCs,but the mechanism needs to be further studied. The new bioreactor can solve the problem of low degradation efficiency for hydrophobic VOCs,such as two-phase distribution bioreactors Reactors (TPPBs),membrane bioreactors (MBR),and bioelectrochemical systems (BESs),etc.,but the cost and energy consumption of the entire degradation process are high,relevant research needs to be strengthened.