We investigate the nonlinear third-order polarizabilities of novel sandwichlike clusters [Al4MAl4]n− (n = 0–2, M = Ti, V and Cr). The calculations have been performed by employing time-dependent density functional theory combined with sum-over-states method. The results show that these complexes possess remarkably large third-order static polarizability, and change of a metal centre has a great influence on the third-order nonlinear optical properties. The calculated third-order polarizability follows: [Al4CrAl4] > [Al4VAl4]− > [Al4TiAl4]2−. Analysis of the main contributions to the third-order polarizability suggests that charge transfer ( $${\rm Al}_{4}^{2-} \rightarrow {\rm M}$$ ) along the z-axis direction plays a key role in the nonlinear optical response.