Based on the distribution and hydrocarbon compounds of the natural gas, along with the alteration characteristic of the salinity of formation water, the distribution of the reservoir bitumen and the biomarkers in the deep formations, the effective migration pathways and the migration direction of the deep gas in Bonan—Gubei area have been studied in this text. And the study demonstrates that oiltype gas generated from the deep zone of Bonan subsag migrates towards the Gubei buried hill area along the migration pathways including the Guxi fault and the unconformities; while the coaltype gas from the lower parts of the Gubei buried hill migrates from north to south along the sands bodies in the fault block. The sand bodies are cutted out by the south—north faults. At the same time, the geochromatography effect of petroleum coming from the Es4 in Bonan subsag is different, which indicates that the migration distance is different.