The effect of elevated carbon dioxide concentration ([CO 2 ]) on fertilizer nitrogen (N) recovery in wheat grown under open-air conditions in the North China Plain has not been reported. Winter wheat (Triticum aestivum L. cv. Zhongmai 175) was grown to maturity under ambient (415±16μmolmol −1 ) and elevated (550±17μmolmol −1 ) [CO 2 ] at the free-air carbon dioxide enrichment (FACE) facility in a semi-arid region in northern China. We applied 15 N-enriched (10.22at.%) granular urea to microplots at either 25 or 95kgNha −1 at the stem elongation stage of wheat. Elevated [CO 2 ] increased wheat biomass (29%) and grain yield (23%), but had no significant effect on grain protein concentration. The [CO 2 ]-induced N demand (19%) was satisfied mostly by increased uptake of indigenous N (19%). Elevated [CO 2 ] had no significant effect on the recovery of fertilizer 15 N (applied at stem elongation) by the plant or on the amount that remained in the soil. Of the fertilizer 15 N assimilated by the whole plant, the allocation to grain increased from 62% under ambient [CO 2 ] to 72% under elevated [CO 2 ]. High N application did not increase wheat biomass, grain protein concentration, or fertilizer N recovery in the plant, irrespective of [CO 2 ]. The results suggest that current fertilizer practice in a wheat cropping system such as in the North China Plain will have to be adjusted in a CO 2 -rich world.