Compressed Air Energy Storage (CAES), a widely applied energy storage technology, is regarded as a promising approach to ameliorate the shortage of renewable energies. However, the efficiency of CAES is limited due to the throttling process in the system, which results in exergy losses. To avoid the influence of throttling effect, a closed isobaric compressed air energy storage (CI–CAES) system was proposed to improve the performance of CAES technology. In this new system, the low-pressure underground storage tank achieves higher inlet pressure of compressors compared with conventional CAES systems, and constant air pressure in the high-pressure underground storage tank leads to stable power output. In addition, industrial waste heat is utilized to increase the inlet temperature of turbines. The trade-off between thermodynamic performance and economic performance is investigated by a multiobjective genetic algorithm, where 65.98% and 1.12 k$/kW are selected as optimal solutions for the two objectives.