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Few studies have investigated how the reclamation of the desert to cropland affects soil nitrous oxide (N₂O) emissions. A study site was initiated in 2005 at the southern Taklimakan Desert by establishing four fields along the desert−oasis ecotone. Three fields were reclaimed as croplands for continuous cotton (<i>Gossypium hirsutum</i> L.) production and received (1) high, (2) low, and (3) no fertilizer inputs and the fourth field remained as a native desert. Static-chamber monitoring of N₂O flux was conducted from April 2019 to March 2021. N₂O emissions occurred in cropland mainly after drip fertigation during the growing season. The two−year N₂O emissions in the desert, no fertilizer, low fertilizer, and high fertilizer were 248, 670, 2232, and 3615 g N ha⁻¹, respectively. The native desert was a weak source of N₂O emissions, with the non−growing season emissions accounting for 66% of the annual emissions. N₂O emissions from farmland mainly occurred over the growing season, accounting for 73−98% of the total annual emissions. The N₂O flux was positively related to soil NO₃⁻−N concentration and soil water−filled pore space (WFPS), highlighting the importance of soil N availability and moisture in affecting N₂O emissions in extremely arid areas. Our results demonstrate that land reclamation from the desert to cropland significantly increased N₂O emissions due to high nutrient inputs. Thus, appropriate fertilizer management in the reclaimed land is essential for maintaining yield, improving soil quality, and reducing N₂O emissions for continuous cotton production.