The East Siberian Arctic Shelf (ESAS) is a significant source of atmospheric methane, and the coastal Laptev Sea near the Lena River Delta is a documented hotspot for methane seepage. While anaerobic oxidation of methane (AOM) acts as a critical biofilter, the specific pathways and electron acceptors driving this process in the unique river-influenced settings of the Arctic remain poorly understood. The Lena River delivers substantial terrigenous nutrients to this region, contributing approximately 10 % of the total riverine nitrogen and 17 % of the iron input to the Arctic Ocean. This study examines the hypothesis that these nutrient fluxes play a crucial role in regulating AOM, a key process mitigating methane emissions. We compared the geochemical conditions at active methane seep sites and background areas, with a special focus on nitrogen and iron compounds in bottom and pore waters.Our geochemical investigation reveals three key findings: (1) Methane concentrations were substantially elevated at seep sites (up to 3118 nM) compared to background areas (as low as 5.5 nM) and showed negative correlations with nitrate (NO₃⁻) and iron (Fe) concentrations. (2) A clear decoupling of the FeMn cycles at seep sites, which was absent in background sediments, indicates the preferential utilization of reactive iron oxides in AOM (Fe-AOM). (3) A severe depletion of bioavailable nitrogen species was observed in seep zones, where nitrate and nitrite concentrations were 5.5-fold and 2-fold lower, respectively, than in background areas, suggesting active nitrate/nitrite-dependent AOM (N-AOM).These findings demonstrate that on the nutrient-rich, river-influenced Laptev Sea shelf, AOM is primarily driven not by canonical sulfate reduction, but by the reduction of nitrogen species and iron. This newly identified coupling between riverine nutrient fluxes and AOM pathways represents a critical, yet previously overlooked, mechanism that could significantly suppress methane emissions from climate-sensitive Arctic shelves. To our knowledge, this study provides the first comprehensive investigation of nitrogen and iron transformation mechanisms coupled with methane oxidation at the water-sediment interface in the cold seeps of the coastal Laptev Sea shelf.