Equipment　used　in　underwater　sensing　and　exploration　typically　relies　on　cables　or　batteries　for　energy　supply,　resulting　in　a　limited　and　inconvenient　energy　supply　and　marine　environmental　pollution　that　hinder　the　sustainable　development　of　distributed　ocean　sensing　networks.　Here,　we　design　a　deep-sea　differential-pressure　triboelectric　nanogenerator　(DP-TENG)　based　on　a　spiral　shaft　drive　using　modified　polymer　materials　to　harness　the　hydrostatic　pressure　gradient　energy　at　varying　ocean　depths　to　power　underwater　equipment.　The　spiral　shaft　structure　converts　a　single　compression　into　multiple　rotations　of　the　TENG　rotor,　achieving　efficient　conversion　of　differential　pressure　energy.　The　multi-pair　electrode　design　enables　the　DP-TENG　to　generate　a　peak　current　of　61.7　μA,　the　instantaneous　current　density　can　reach　0.69　μA　cm−2,　and　the　output　performance　can　be　improved　by　optimizing　the　spiral　angle　of　the　shaft.　The　DP-TENG　can　charge　a　33　μF　capacitor　to　17.5　V　within　five　working　cycles.　It　can　also　power　a　digital　calculator　and　light　up　116　commercial　power　light-emitting　diodes,　demonstrating　excellent　output　capability.　With　its　simple　structure,　low　production　cost,　and　small　form　factor,　the　DP-TENG　can　be　seamlessly　integrated　with　underwater　vehicles.　The　results　hold　broad　prospects　for　underwater　blue　energy　harvesting　and　are　expected　to　contribute　to　the　development　of　self-powered　equipment　toward　emerging　“smart　ocean”　and　blue　economy　applications.　©　2024　The　Authors