The effects of S impurities, both interstitial and substitutional, on adhesions at Al2O3/Ni and ZrO2/Ni interfaces were investigated with the first-principles method. The effects of S impurities on the adhesion of the Ni/Al2O3 interfaces are quite obvious, and changes in equilibrium adhesive energies evidently range with the type of impurities. The effects of S impurities on the adhesion of the Ni/ZrO2 interface are very slight. For the two interfaces considered, both interstitial and substitutional S impurities will increase their equilibrium interfacial distances. (C) 2003 Elsevier B.V. All rights reserved.