The adsorption of H2 on CO‐covered Ni films was investigated in the temperature range of 77 to 273 K by means of measuring the change in resistivity, the change in work function, isotherms and isosteric heats of adsorption. – At 77 K molecular H2 is only physically adsorbed on a CO covered Ni film with a minor increase in resistivity. H2, atomised by a hot tungsten filament, is readily adsorbed on a CO layer at 77 K, the accompanying change in work function is −1.45 eV. – Molecular H2 is adsorbed on a CO‐covered Ni film in the temperature range of 180 to 273 K with a decrease in resistivity and a temperature dependent decrease in work function. The maximum change in work function is −80 mV at 185 K and 5 · 10−2 Pa. The initial isosteric heat of adsorption of H2 is 36 ± 2 kJ/mol, which decreases slowly with increasing coverage.