Abstract: According to the international stratigraphic chart of 2004, the Fusulinid fossil zones close to the boundary of Carboniferous and Permian in some known sections in the Xing’an-Mongolia and Jilin-Heilongjiang orogenic belt can correlate to the typical sections in Southwest China. There are three typical Carboniferous and Permian boundary sections in the region. They are Huangyu section in Yongji, Jilin Province, Guangpigushan section in Shuangyang, Jilin Province, and Mihangaoqiaogaolu section in Xiwuqi, Inner Mongolia. All these three sections develop carbonate facies at the boundary of Carbonife-rous and Permian. The Fusulinid zone, represented by Pseudoschwagerina uddeni or Pseudoschwagerina borealis overlies Triticites zone in the region. The feature is the similar to sections in Luodian and Ziyunchang in Guizhou Province, and Yishan section in Guangxi Province. So the authors consider that the bottom of Pseudoschwagerina uddeni zone to be the boundary of Carboniferous and Permian.

Key words: reference section, Carboniferous, Permian, Xing’an-Mongolia and Jilin-Heilongjiang orogenic belt