Effect of VI group elements (O, S, Se, Te) modification on the electronic properties of two-dimensional AlN were investigated by first-principles calculation method using density functional theory. The calculation results indicate that after O modification, the energy bands of the two-dimensional AlN system undergo splitting, thereby transforming into magnetic materials. After modification with S, Se and Te, the electron density of states curves of the two-dimensional AlN exhibit complete spin up and spin down symmetry, forming a non-magnetic structure. From the density of states graph, it can be seen that the density of states near the Fermi level is mainly contributed by the p-state electrons of the modified atom and the p-state electrons of the N atom. The bottom of the conduction band gradually moves towards the lower energy region, causing the absorption wavelength threshold of two-dimensional AlN to shift from the ultraviolet region to visible light. Therefore, the modified two-dimensional AlN improves its photocatalytic efficiency and has the potential to be used in the visible light responsive optoelectronic and spin electronic devices.