In the process of gas well exploitation, problems such as pressure at the wellhead are encountered after the cement stone isolation fails, which seriously affects the safety production of gas wells. In view of the isolation problems in the natural gas exploitation process in Tarim Oilfield, this paper combines the mechanism of self-healing gas-recovering materials developed in the laboratory to design the cement stone fracture and self-healing evaluation methods, and explores the self-healing suitable for natural gas well isolation. The main method is to use micro scanning technology to observe the micro-crack healing and the expansion effect of the internal self-healing material. The gas self-healing material has a good sealing effect after the micro-fractures in the core. The micro-fracture permeability decreases from 1 . 9985 mD to 0. 01480mD at the initial moment with a decrease of more than 99. 26% . The micrographs of the end face and interior of the core show that the self-healing material particles gradually change from white to light yellow, which means to expand and heal.The results show that this kind of self-healing material can be applied to the healing and sealing of natural gas wells after Micro-fractures.