Abstract: FACE platform was applied to study the effects of elevated atmospheric CO₂ concentration on wheat grain yield and quality under two nitrogen(N) application rates. Elevated atmosphericCO₂ concentration and applying N increased the grain yield, spike number, grain number per spike, and biomass significantly, but elevated CO₂ concentration had no significant effects on harvest index (HI). Under elevated CO₂ concentration, there was a significant decrease in the protein, gliadin, gluteinin, and glutein contents of the grain and the sedimentation value of the flour, and a significant increase in the starch and its components contents of the grain; under N application, an inverse was observed. The dough stability time and the dough viscosity characteristics, such as peak viscosity, final viscosity, and setback value, increased significantly under elevated CO₂ concentration and high N application rate. The interaction of atmospheric CO₂ concentration and N application rate had significantly positive effects on wheat grain yield and  biomass, but less effect on grain quality. Therefore, with elevated atmospheric CO₂ concentration in the future, maintaining a higher N application level would benefit wheat grain yield and paste characteristics, and mitigate the decline of grain quality.

Key words: wheat, yield, quality, FACE, nitrogen fertilizer