Generally, logging curve shape and logging data are generally used to identify and evaluate the reservoir and caprock in the study of reservoir-caprock assemblage in conventional logging method, which fails to distinguish the reservoir-caprock assemblage and allocation relation of different producing layers (high and low production gas layer, dry layer). In order to analyze and discriminate the types of reservoir-caprock assemblage and the corresponding productivity quickly and accurately, the dual logging parameter method is put forward to study reservoir-caprock assemblage and predict its productivity. Besides, discrimination standard and allocation relationship of reservoir-caprock assemblage determined by the dual parameters of reservoir porosity and caprock porosity are also established.