To enhance the anti-corrosion and antifouling capabilities of 9 442 copper alloy in marine environment, a nanosecond laser surface treatment was employed to induce a hierarchical micro/nano composite structure, resulting in superhydrophobic surfaces with contact angles exceeding 150°. Electrochemical corrosion tests on these surfaces, treated with varying laser powers, revealed that at 100 W, the corrosion current density decreased to 7.323×10^-7 A·cm^-2, achieving a 70.0% corrosion inhibition efficiency compared to untreated copper alloy. Additionally, offshore antifouling performance tests demonstrated that the superhydrophobic surface exhibited superior antifouling and corrosion resistance, with minimal component corrosion, highlighting its practical application potential in marine environments.