Abstract: 　　
　　Objective To address the challenges of helium storage given helium’s scarcity and stringent sealing requirements, this study evaluates the sealing performance of bedded salt cavern helium storage and optimizes its operating pressure to enhance underground helium storage safety and efficiency. Methods Helium permeability in salt rock and interlayer samples was first measured under a confining pressure of 30 MPa using steady-state experiments, providing key parameters for numerical modeling. A salt cavern helium storage seepage model was then developed to simulate helium flow and leakage under various operating pressure conditions, and a multi-objective analysis was conducted to determine the optimal pressure range that balances sealing integrity and storage capacity. Results Experimentally, helium permeability in salt rock (~7.58×10⁻²¹ m²) is orders of magnitude lower than that in interlayer (~1.31×10⁻¹⁷ m²), confirming the superior gas-tightness of salt rock. Numerical simulations indicate that over a 30-year operation, helium leakage increases with higher minimum operating pressure: the cumulative leakage is about 11.6% at a pressure range of 8–21 MPa and about 12.6% at 10–21 MPa, while a higher lower-limit pressure yields greater working gas capacity. Considering both leakage control and storage efficiency, the 9–21 MPa pressure range offers the optimal compromise. Conclusion Bedded salt formations exhibit excellent inherent sealing for helium; within an appropriate pressure range, helium leakage can be limited to ~12% over 30 years while maximizing storage efficiency. These findings provide important guidance for the design and safe, efficient operation of helium storage in salt caverns.