Oxygen minimum zones (OMZs), such as those found in the eastern South Pacific (ESP), are the most important N2O sources in the global ocean relative to their volume. N2O production is related to low O 2 concentrations and high primary productivity. However, when O 2 is sufficiently low, canonical denitrification takes place and N2O consumption can be expected. N2O distribution in the ESP was analyzed over a wide latitudinal and longitudinal range (from 5°to 30°S and from 71-76 °to ∼ 84 °W) based on ∼ 890 N 2O measurements. Intense N2O consumption, driving undersaturations as low as 40%, was always associated with secondary NO 2– accumulation (SNM), a good indicator of suboxic/anoxic O2 levels. First, we explore relationships between δN 2O and O2 based on existing data of denitrifying bacteria cultures and field observations. Given the uncertainties in the O2 measurements, a second relationship between δN2O and NO -2 (> 0.75 μM) was established for suboxic waters (O2 < 8 μM). We reproduced the apparent N2O production (ΔN2O) along the OMZ in ESP with high reliability (r2 = 0.73 p = 0.01). Our results will contribute to the quantification of the N2O that is recycled in O2 deficient waters, and improve the prediction of N2O behavior under future scenarios of OMZ expansion and intensification.