We evaluated the effects of elevated O₃ and different N fertilization on soil nematode communities in a wheat field using the open top chambers (OTC) in National Field Research Station of Shenyang Agroecosystems. The results showed that (1) elevated O₃ decreased the root biomass at wheat ripening stage. The interactive effects between elevated O₃ and N fertilization changed soil microbial biomass carbon (MBC), microbial biomass nitrogen (MBN) and dissolved organic carbon (DOC) at ripening stage, which were decreased by the elevated O₃ under low nitrogen treatment and increased under high nitrogen treatment. (2) Elevated O₃ and N fertilization did not affect the total nematode abundance. While at wheat filling stage, nematode functional guilds belonging to bacterivores and fungivores with c-p 4 values (Ba 4 and Fu 4) were sensitive to elevated O₃ and N fertilization. At wheat filling stage, the numbers of Ba4 were decreased in the elevated O₃ treatments in comparison with control, this trend regardless of N conditions. Following the elevated O₃, the functional guilds of Fu4 were increased in high nitrogen treatment, while decreased under low nitrogen treatment at filling stage. (3) Analysis of the ecological indices indicated that effects of elevated O₃ and N fertilization might change the structure of soil micro-food web. Following elevated O₃, nematode maturity and structural indices were decreased under low nitrogen treatment and increased under high nitrogen treatment, which suggest that high nitrogen fertilization may relieve the disturbance of elevated O₃ on soil micro-food web.