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Greenhouse gases (GHGs) trapped in ice wedges may provide useful information on biogeochemical environments in ground ice. Previous studies have reported highly elevated CO₂ and CH₄ mixing ratios in ice wedges. However, N₂O mixing ratios in ice wedges remain unknown. Here, we present CO₂, CH₄ and N₂O mixing ratios in bubbles and plausible mechanisms of GHG formation for two lakeside ice wedges at Cyuie village near Yakutsk. The CO₂ gas age corresponds to the Last Glacial Maximum (18–19 ka). The δ(N₂/Ar) values and bubble shapes indicate that the ice wedges formed by dry snow compaction rather than snowmelt water refreezing, while the δ¹⁸O and δD values of the ice indicate changes in the source area location and/or the climate during the Last Glacial Maximum. Using a dry extraction method, we obtained gas mixing ratios of 7–13% CO₂, 5–130 ppm CH₄ and 100–5000 ppb N₂O …