To explore new pathways of CO2 geological storage, the mechanism of CO2 stored in abandoned coal mine gob was analyzed through the investigation of the gobs exploitation current situation. Methods to calculate the capacity to store CO2 was proposed based on establishing mathematical model. This paper presented suggestions about how to carry out research in the future. Research suggests that after the coal mine is abandoned, there are large underground spaces consisting of rock cavities of gob caving zone, rock fissures of fractured zone, and permanent residual laneways, which CO2 can be stored, and there will be tremendous sequestration potential. Compared with deep aquifers storage, the space has the advantages of larger scale porosity, simpler storage mechanism, easier injection, more abundant geological data, etc. At the same time, the space also remains problems such as lower seal strength and failure of overburden strata easily causing CO2 leaks, etc. This paper suggests that six aspects should be further researched in the future.