Norway spruce seedlings were grown under greenhouse conditions in Rootrainers with a peat-vermiculite mixture under elevated N loads for six months. Seedlings were inoculated with ectomycorrhizal fungi, either Hebeloma crustuliniforme or Cenococcum geophilum, and supplied with a 1:5 diluted nutrient solution. Nitrogen was applied as ammonium nitrate in loads of 0 (control), 50, 100, or 400 N/ha/y. The addition of N significantly increased shoot and root biomass of the seedlings, whereas the root/shoot biomass ratio and the ectomycorrhization were significantly decreased. The ectomycorrhization with H. crustuliniforme decreased from 100% at 0 kg N/ha/y to about 50% at 400 kg N/ha/y, and that with C. geophilum decreased from 35% with 0 to 5% with 100 kg N/ha/y. At 400 kg N/ha/y, the formation of ectomycorrhizas by C. geophilum was suppressed. While N concentrations in shoots and roots increased significantly with enhanced N loads, P and Zn decreased significantly. The inoculation with H. crustuliniforme compared with C. geophilum very significantly increased the P concentrations in roots and the Zn concentrations in shoots, whereas it significantly decreased Mn concentrations in shoots and roots.