Abstract: The scale of oil-gas resources undiscovered in mature hydrocarbon province is greatly paid attention to.This paper presents a pool size sequence method and estimates the remaining petroleum resources in Jinhu sag with the total amount of the resources of 10 802×104 t and their distribution in nearly 159 reservoirs, of which the undiscovered resources amount to 4 038×104 t, distributing in about 58 reservoirs.Although it has a higher extent of exploration in this area, there still exist some potential for petroleum prospecting.A great number of medium-small-sized pools will be as key targets for further exploration in the future.The pool size sequence method can be applied to make a prediction of the petroleum resources by way of simple procedure, and is of a broad application prospect.

Key words: Jinhu sag, petroleum resources, assessment, size, sequence