X-ray photoelectron (XPS) and X-ray Auger electron spectroscopy (XAES) were used for investigating the chemical and structural states of various aluminates. A clear chemical shift in Al modified Auger parameter (AP) for coordination state of Al atom was observed. For similar chemical composition, the AP of tetrahedral Al was higher than that of octahedral Al. In the same coordination state, the AP became larger by the following order; Al oxide ≈ Al double oxide < Al phosphate ≈ Al hydroxide < Al silicate. This order correlated with an electron affinity of secondary coordinated cations. On the other hand, the effective electrostatic force of Al-O calculated by bond strength showed a correlation with the AP of the samples except for several aluminosilicates. Since these aluminosilicates have solid acidity, the deviation from the correlation may be used as an index of solid acidity in Al sites.