Abstract: Through analyzing the subsurface space and time characteristics of geological storage of carbon dioxide and considering the characteristics of environmental isotopes,the following three aspects are presented when environmental isotopes are used in carbon storage:(1) hydrogeological conditions of the carbon dioxide sequestration site are identified and safety durability of typical salt water layer in which carbon dioxide is sealed and its suitability to store carbon dioxide are evaluated; (2) determining the isotope methods to recognize the “leaked carbon source”and the leaked“carbon” source; (3) with the environmental isotope technique, the relationship between groundwater circulation and CO2 geological storage is examined, and the potential leakage of carbon dioxide sequestration effect on the shallow aquifer is evaluated.