Abstract: From the hydro-geochemical studies on the rules of oil and gas accumulation, this paper has concluded that to delineate favorable region of rich oil and gas, first of all, we have to identify the relationship between the petroliferous basin and artesian basin in the geologic history of the development process following the research principle from regional to local. Secondly dividing of water-bearing rock series provides a basis to study the groundwater movement and the chemical composition of water, and then we can integrate water power and water chemistry as a comprehensive study of unified field. In addition, we have to obtain reliable information and analysis of water samples. Effective water-chemical parameters selection is also a necessary condition to study the chemical composition of water and the relationship of composition with the oil and gas.