The crystal quality of InAlSb/InSb film materials may directly affect the performance of the eventual detection devices. To improve the crystal quality of film materials not only can reduce the dark current of detection devices, but also can improve the detectivity and uniformity of them. The preliminary result of a Molecular Beam Epitaxy (MBE) method for aluminum-doped InSb materials is reported. The crystal quality of the InAlSb film grown by MBE is analyzed by using a variety of test and analysis methods. The factors which have influence on the crystal quality are found out and the technical level of the MBE of InAlSb film materials is improved. The experimental result shows that through optimization of the growth conditions such as growth temperature, beam ratio, cooling rate and annealing process, high quality MBE InAlSb film materials can be obtained.