The identification of deep thermal fluid activity and its effect on hydrocarbon accumulation has become a hot topic in petroleum geology research. There are many methods to identify thermal fluid activity, and its influence on hydrocarbon accumulation is also more complex. In view of this, based on a large number of literature research, this paper summarizes the identification methods of hydrothermal fluid activity, and systematically combs the influence of hydrothermal activity on hydrocarbon accumulation. According to the summary and analysis, the main identification methods of hydrothermal fluid activities can be summarized into three types, namely, rock-mineral characteristics combination identification method, temperature sensitive parameter anomaly method and geochemical element content anomaly method. The current mainstream methods include rock-mineral characteristics combination identification method, fluid inclusion homogenization temperature identification method and vitrinite reflectance mutation method. In the specific implementation, a variety of methods should be selected as far as possible for comprehensive identification. The influence of hydrothermal fluid activity on hydrocarbon accumulation is reflected in four aspects: deep hydrothermal fluid creates good conditions for the formation of hydrocarbon substances by providing thermal energy, exogenous hydrogen and catalyst required for the maturation and evolution of source rocks, the influence of hydrothermal fluid on oil and gas reservoirs maybe constructive or destructive, but mainly of the constructiveness of hydrothermal dissolution, deep fluid can enhance the sealing ability of caprock, hydrothermal fluid promotes hydrocarbon generation of source rocks, forming hydrocarbon generation pressurization to promote the primary migration of oil and gas, the dissolution by thermal fluid changes the physical properties of reservoirs and can promote the secondary migration of oil and gas. This study summarizes the influence of hydrothermal fluid activity on hydrocarbon accumulation in detail, which can provide reference for the study of hydrocarbon accumulation conditions transformed by deep hydrothermal activity in sedimentary basins.