Nitrous oxide (N₂O), a potent greenhouse gas, is produced and reduced mainly under the mediation of functional microorganisms in soil. In terrestrial ecosystems, soil is an important source of N₂O emission. Soil aggregates, a key structural component of the soil, consist of sand, silt, clay (primary particles), organic matter (binding agents) and pore spaces. According to the hierarchy theory, soil aggregates can be divided into four fractions by size, that is, large macroaggregates (>2 mm), small macroaggregates (2-0.25 mm), microaggregates (0.25-0.053 mm) and silt plus clay-sized particles (<0.053 mm). Large macroaggregates are high in pore connectivity and oxygen diffusion rate, fast in turnover, and rich in organic matter, and microaggregates high in water retention capacity and stable carbon content, and capable of protecting microorganisms from being predated. Hence, soil aggregates different in size may offer heterogeneous microhabitats for fungi and bacteria. And each independent microhabitat could be regarded as a biogeochemical reactor producing greenhouse gas. Nitrifiers and denitrifiers, which carry functional genes amoA, narG/napA, nirK/nirS, are identified as the major contributors to N₂O production. However, N₂O reduction is primarily a single process catalyzed by N₂O reductase, encoded by nosZI and nosZII genes, which are present in bacteria and archaea capable of complete denitrification and acting as non-denitrifiers in N₂O reduction to N₂. These microorganisms are distributed separately in polymerized reactors different in size, driving N₂O production and transportation as affected by soil moisture status, substrate availability, and porous connectivity. However, so far little is known about community structure of the nitrifiers and denitrifiers in aggregates relative to particle size and its influences on N₂O emission. Nowadays, a numerous of studies have been reportedly devoted to soil N₂O emission characteristics in different ecosystems, but limited knowledge was achieved on N₂O emission and relative contribution of soil aggregates relative to size fraction. Therefore, with the clarification of functional microbial distribution at the aggregate scale, hot-spots of N₂O production and reduction in soil microhabitats could be specified. In this review, advances in the recent research are summarized on divergence of N₂O emission from soil aggregates. Large macroaggregates and small macroaggregates were found emitting more N₂O than microaggregates did. However, studies were also found reporting conversely that microaggregates emitted N₂O more vigerously. Papers in the literature also reported relationships between aggregate turnover(the formation, stabilization and disintegration of soil aggregates)and microbial structure dynamics. Bacteria contribute strongly to the formation of both macro- and microaggregates, while fungi play an important role in the formation of large macroaggregates. Hence, the mechanisms of soil microbes producing and reducing N₂O in soil microhabitats could be summed up. A large number of studies have shown that ammonium oxiders are abundant in macroaggregates (>0.25 mm) and a dominant denitrifier community in microaggregates (<0.25 mm), and environmental factors affect N₂O emission via redistributing these functional microorganisms. Based on the current results, discussions are done of some perspectives for future investigations: potential hot-spots for soil N₂O production at the aggregate scale as heterogenetic living niches existing in soil aggregates different in size, critical values of key environmental parameters impacting soil N₂O production and reduction, and holistic research on functional gene groups and enzymes instead of some individual gene due to the complex participation of soil microbes in N₂O production and reduction. It is expected that this study will provide a reference for modeling and parameter optimization and a solid theoretical basis for mitigation of N₂O emissions.