Abstract: The classification system of Mineral resources reflects,at some extent,he technology level of mineral exploration and development and the background of the nation and corporation who established it.In general,whether on solid minerals or oil and gas reservoirs,the entities of classification establishment could be sorted in three major groups and five societies.But the objects are the same in two aspects:measuring the resources and reserves appropriately,and communicating the standards between different entities.Since the backgrounds in polity,economy,technology and culture of different countries are various,the standopints,the considerations are various,and the outcomes various as well.So far there is only a consistency in the definitions of proved developed reserves for oil and gas over the worldwide government entities and petroleum industry.