The paper chooses the secondary tectonic units of Sichuan Basin as the evaluation object, and considers regional crustal stability conditions, basic geological conditions, reservoir and cap rock conditions, storage potential conditions, geothermal conditions, research degree and potential resources conditions, social and economic conditions as first-level indexes. Based on collected data and a comprehensive analysis of 16 level-two indexes and 9 level-three indexes, and with the application of comprehensive index method, the conclusions regarding the suitability partition of the secondary tectonic units of Sichuan Basin are as follows: Central Sichuan low-flat structural belt is highly suitable for carbon dioxide geological storage, West Sichuan low-slope structural belt is relatively suitable, and SW low-slope structural belt is unsuitable for carbon dioxide geological storage, South Sichuan low-slope structural belt is relatively unsuitable, whereas East Sichuan high-slope faulted fold belt, and North Sichuan low-flat structural belt are fairly suitable for carbon dioxide geological storage. Based on the above, with a comprehensive analysis of corresponding hydrographic and geological conditions, and at the same time considering the non-cov- ered oil or gas resources and the buried structure, six CO₂ geological target formations are identified, including lower Jurassic Ziliujing Group, upper Triassic Xujiahe Group, middle Triassic Leikoupo Group, lower Triassic Jialingjiang Group and Feixianguan Group, and lower Permian Qixia Group. This paper provides an important guidance and reference for the selection criteria of CO₂ geologic storage sites in Sichuan Basin.