Abstract: According to structural features of a compressed-air energy storage (CAES) system, six parameters of the system were experimentally designed and numerically simulated based on orthogonal method, such as the compressor adiabatic efficiency, inter-stage cooling temperature, minimum operating pressure of storage volume, regenerator effectiveness, expansion turbine adiabatic efficiency and combustion chamber efficiency etc., and subsequently an exergy analysis was conducted to the simulation results, while an analysis of variance was carried out to the experimental results to study the effects of above design parameters on the exergy efficiency of the system. Results show that the exergy efficiency of CAES system is mainly affected by the significant parameters, such as the compressor adiabatic efficiency, the inter-stage cooling temperature, the regenerator effectiveness, as well as the interactions between the compressor adiabatic efficiency and inter-stage cooling temperature, the inter-stage cooling temperature and regenerator effectiveness, and between the compressor adiabatic efficiency and expansion turbine adiabatic efficiency, etc. Under present condition of technology, the exergy efficiency of CAES system can be improved by reducing the inter-stage cooling temperature and increasing the regenerator effectiveness.