<p>More than 721 submarine hydrothermal fields have been documented globally, however, the characterization of hydrothermal systems beneath the ice-covered Arctic Ocean remains poorly constrained. During the 2021 JASMInE expedition, a 369-cm-long sediment core was recovered from the central rift valley of the Gakkel Ridge 96°E. The core is predominantly composed of terrigenous debris, Fe-(oxyhydr)oxides, volcanic glass, and hydrogenetic Mn oxides. Three hydrothermal-affected layers (HA1–HA3) within the upper 85 centimeters below seafloor (cmbsf) exhibit enrichment in Fe, Cu, Pb, P, V, Mg, Ca, and Na, associated with accumulation of Fe-(oxyhydr)oxides and volcanic glass. Among these, Layer HA2 (13–16 centimeters below seafloor (cmbsf)) displays the most intense hydrothermal signature, characterized by high concentrations of Fe (12.06–15.22 wt.%), Mn (2 687–5 465 μg/g), Cu (245–373 μg/g), and Pb (248–342 μg/g), accompanied by reduced rare earth element (REE) concentrations, and shalenormalized patterns featuring negative Ce anomalies, and positive Eu anomalies. In comparison, Layers HA1 (83–85 cmbsf) and HA3 (6–7 cmbsf) exhibit only marginally elevated concentrations of hydrothermal-related elements (Fe, Cu, Pb, P, V) compared to pelagic background sediments, indicating a weaker hydrothermal influence. Overall, the observed coarsening of volcanic glass grain size and its increased abundance within hydrothermal-affected layers, coupled with diagnostic signatures from the Al- Fe-Mg ternary diagram and the detection of hydrothermal plume anomalies along the 100° E Axial Volcanic Ridge (AVR), collectively point to a basalt-hosted hydrothermal system associated with the AVR as the source of the hydrothermal signals recorded in the core. These findings reveal the geochemical fingerprints of hydrothermal materials in Arctic deep-sea sediments, offering new insights into their sources and formation processes in the ice-covered ocean.</p>