The CO2 storage capacity of saline aquifers is a basic issue related to China's goal of carbon neutrality. The Sichuan Basin is an important oil and gas producing area in the southwest of the country, but there is still a lack of in-depth quantitative research on the CO2 storage prospects in its deep saline aquifers. The Leikoupo Formation T2l is a high-quality brine reservoir in the Sichuan Basin, and its fourth member T2l4, third member T2l3, and first member T2l1 can be used as target reservoirs for CO2 sequestration. In this study, based on the analytical solution to the overpressure induced by multiwell simultaneous injection, the MATLAB language script named CO2BLOCK is used to evaluate the CO2 storage capacity of the deep saline aquifers in the Leikoupo Formation. The results show that under the condition of continuous CO2 injection for 30 years, the CO2 storage capacity of the Leikoupo Formation reservoir in the Sichuan Basin is 0.83Gt, among which the storage capacity of the fourth member of Leikoupo Formation is the largest, the first member of Leikoupo Formation is the smallest. The maximum sustainable injection rate per well in the fourth, third and first members of the Leikoupo Formation are 0.550Mt/a, 0.051Mt/a and 0.054Mt/a, and the corresponding maximum sustainable overpressures are 3.09MPa, 5.67MPa and 6.55MPa. The economic optimal schemes (number of wells, well spacing) of the three reservoirs T2l4, T2l3 and T2l1 are respectively: (16,17), (20,17), (16,19), and the storage capacity corresponding to the economical optimal well arrangement scheme are 0.50Gt, 0.07Gt, 0.04Gt.