Abstract: The metamorphic zone of coal series in Carboniferous-Permin of the north China Platform are divided using abundant data of vitrinite reflectance. The burial depth and geotemperature are important factors which have a dominant influence over thermal evolution. Petroleum generation in coal series is closely related to the metamorphic zone of coal series. The Permian-Triassic coal series in the moderately-highly metamorphized zones usually have an early generated petroleum which would have been lost unless there are any good covering strata; while the moderately-highly metamorphic Cenozoic zones and their neibouring areas have a late generated petroleum, and they usually have promising prospects.