Abstract Adsorption of oxygen and carbon monoxide on smooth and sputtered clean surfaces of epitaxial Pd(111)/mica films was studied. Electron beam irradiation effects on the adsorbates were important only for CO in the total dose range of 1×10 14 to 2×10 19 electrons/mm 2. The cross section for beam damage was approximately 2×10 -17 mm 2/electron for the CO ad/Pd(111) system. AES was used to measure the O(KVV)/Pd(M 4,5VV) intensity ratios for both O and CO adsorbates. Saturation values of 0.017±0.001 and 0.016±0.001 were obtained for O and CO respectively. The value for O is significantly lower than for sputter etched and annealed bulk crystals. No values have been reported for CO. On sputtered thin film surfaces, these ratios saturated at somewhat higher values when saturation ion doses were applied. The saturation ion dose was approximately 3×10 13 ions/mm 2. Beyond this value no additional oxygen or carbon monoxide could be adsorbed. Annealing returned the adsorption characteristics to what was obtained on the initially smooth surfaces.