The geometrical structures,relative stabilities,electronic structures and bonding properties of AlB+n(n = 2~10) clusters have been investigated by using the density functional theory at the level B3LYP/6-311G(d).With the most stable structures obtained,it shows that the boron atoms are more likely to get together,remaining the Al atom lying around the boron-atom group.Compared to the neutral clusters,the effect of Al-B bonds becomes weaker,which leading to a relative bigger change of geometry to neutral clusters when n=2~4 and n=7~10.Via calculating the energy gap for both positive charged and neutral clusters,we found that the stability of AlBn+ (n = 2~10) clusters enhances,especially for AlB+3,AlB+5 and AlB+8 clusters.Infrared vibration spectra of the most stable structures are also investigated.The vibration mode with symmetrical or no-symmetrical vibration between B atoms and fixed Al atom are easier to perform a more intense spectral peak.This result indicates that the B atoms should be preferential to bond.