AlGaNb alloy samples were prepared by hot rolling method, and the structural changes and deformation behavior of this process were analyzed. The results show that many flake-like structures are formed in the as-cast Al0.86Ga0.14Nb alloy with the size of 200-240 μm, and γ-phase grains with the diameter of about Φ8 μm are formed in the grain boundary region of lamellar cluster with the α2/γ lamella spacing of 0.3-0.6 μm. Then, AlGaNb alloy with the thickness of close to 1 mm is obtained, and the smooth interface structure is formed. When the lamellae are subjected to hot rolling force, they are deflected and formed with larger spacing to obtain wider γ-slats, and the width of α2 phase is reduced. However, in the initial deformation stage, the stacking dislocation is formed in the lamellae, and the significant dislocation plugging occurs in the γ phase grains. Furthermore, in the subsequent deformation process, the substructure is changed to large angle grain boundary, and the more recrystallized grains are produced. In addition, the twin structures with larger morphologic differences are formed in Al0.86Ga0.14Nb alloy, their widths are relatively larger, and most of the twins are located in the grain boundary region of lamellar structure.