Abstract: In this study, a photovoltaic（PV） hydrogen-production model using salt caverns for hydrogen storage is constructed and its economy is analyzed. First, salt caverns are physically modeled to calculate the hydrogen-storage capacity. Subsequently, a PV hydrogen-production system is constructed, pressure-vessel and salt-cavern hydrogen-storage schemes are set to be analyzed against each other, and the capacity of each scheme is optimized using a mixed-integer planning model for cost minimization. Next, the results of the optimization are analyzed via techno-economics analysis. Finally, a sensitivity analysis is performed for the salt-cavern storage scheme based on four factors. The results show that the levelized cost of hydrogen in the PV hydrogen system using salt-cavern storage is 32.18/kg-H2, which is 8.73% lower than the cost incurred by the pressure-vessel hydrogen-storage scheme. Additionally, the final net present value of the salt-cavern scheme is 20.65% higher than that of the pressure-vessel scheme, with a shorter payback period of 10.14% and a higher internal rate of return. The factors influencing the economy of the salt-cavern hydrogen-storage scheme for PV hydrogen production are, in the descending order, solar irradiation, capital cost of PV and electrolyzer, and salt-cavern burial depth. Therefore, establishing PV-to-hydrogen salt-cavern hydrogen storage in western irradiation-rich areas is more economically feasible in the future when the costs of PV and electrolyzers are lower.