The current CO₂ storage capacity is still far below the requirements of the “carbon peak” and “carbon neutrality” goals. Therefore， the diversified CO₂ underground storage methods play an important role in promoting the realization of dual carbon goals. Based on the summary of the current status of CO₂ underground storage， the distribution spatial pattern of carbon source and sink， the treatment of alkaline industrial solid waste， the CO₂ mineralization capacity of alkaline industrial solid waste， and the underground waste space， a storage method of mineralizing CO₂ using alkaline solid waste， and then transporting it into the underground waste space is proposed， which can realize the goal of “treating waste with waste”. Based on the total amount of underground waste space， the amount of underground waste space within 50km from prefecture-level cities， and the provincial-level distribution of underground waste space， the corresponding storage capacity of alkaline industrial solid waste including fly ash， steel slag， carbide slag storage， and CO₂ were calculated respectively. The storage potential of the aforementioned method was demonstrated from both the total storage amount and spatial distribution pattern. Moreover， further study of this method and the advantages in geological engineering is pointed out.