Kinetics and energetics of hydrogen adsorption on unsupported nickel and nickel supported on silica, alumina, and titania were investigated by means of temperature-programmed desorption. The number and population of adsorption states at moderate to low coverages and heats of adsorption were found to be strong functions of the support. Heats of adsorption ranged from approximately 85 kJ/mole on unsupported Ni and Ni/SiO 2 to 122 kJ/mole on Ni/Al 2O 3. In addition, hydrogen adsorption on Ni/Al 2O 3 was found to be an activated process. Reduction of Ni/TiO 2 at high temperatures (600–700 °C) was observed to strongly suppress the adsorption of hydrogen and shift the TPD spectrum to lower binding energies. Desorption spectra obtained using an N 2 carrier gas were significantly different from those obtained using Ar or He carrier gases probably due to competitive adsorption of N 2 on the nickel surface.