<p>The global ocean is a major source of the climate-relevant atmospheric trace gas nitrous oxide (N₂O). However, an accurate assessment of the global oceanic emissions of N₂O is hampered by missing data on dissolved N₂O from large regions such as the Southern Ocean. To address this deficit, N₂O was measured in the Prydz Bay in February 2015 during the 31st Chinese National Antarctic Research Expedition. N₂O concentrations (saturation) in the surface layer were generally low (undersaturation with respect to atmospheric equilibrium) and ranged from 13.3 nmol/L to 16.1 nmol/L (83%–102%) at the time of sampling. A comparison of our observations with archived data revealed that no discernible trend in N₂O concentrations in the surface waters of Prydz Bay could be detected for the period between 2006 and 2015. Temperature and salinity changes driven by meltwater input were the predominant controls on N₂O concentrations in surface waters. At depth, the distribution of N₂O concentrations was dominated by production via nitrification in offshore deep waters and vertical convection in the shelf waters, where concentrations were lower and gradients were less steep. Our results suggest a rather unusual pattern of N₂O distribution in the Prydz Bay (low N₂O in shelf waters compared with the open ocean), providing important insights into the coastal dynamics of N₂O in high-latitude polar regions.</p>