Bare aluminum cluster ions Al n + ( n ≲ 90) and aluminum-xenon complex ions Xe k-1 Al + ( k ⩽ 24) produced by 7 keV Xe ion bombardment of an Al target have been analyzed using a sector-type mass spectrometer. The abundance spectra of Al n + show intensity anomalies correlating with the electronic shell model for a small size region n ≲ 25; however, for larger clusters the spectra show only monotonic decrease with size. The aluminum-xenon complex ions are detected when the dosage of Xe ions exceeds about 10 19 ions/cm 2. The binding energy and formation mechanism of Xe k-1 Al + are also discussed.