The reduction of gaseous nitrous oxide (N₂O) emissions from wastewater treatment processes is required for the decarbonization of wastewater treatment plants, but the actual fluctuations in N₂O emissions have not yet been clarified. In this study, we conducted continuous monitoring of N₂O emissions from two wastewater treatment processes using an automatic gas analyzer. As a result of continuous monitoring for approximately four months, long-term, medium-term, and short-term fluctuations in N₂O emissions were revealed and the effects of influent water quality were evaluated. The results indicated that N₂O emissions may fluctuate due to the effects of water temperature in the biological reaction tank and influent nitrogen concentration, and that continuous monitoring is effective in clarifying the factors that affect N₂O emissions. Based on these results, it is necessary to review the N₂O emission coefficient and to study operational methods to reduce N₂O emissions.