Aluminum nitride (AlN) nanostructures possess the excellent intrinsic physical properties of AlN, such as wide band gap, high thermal conductivity, high breakdown field strength and excellent thermal stability, as well as the unique physical and chemical properties due to the surface effect and small size effect, gaining widespread attention. After years of hard work and studies, the high quality AlN nanostructures have been prepared, which play the important role in optical, electronic and magnetic fields. Here, the research progresses of the methods for preparing AlN nanostructures are discussed at first, including chemical vapor deposition method, physical vapor transport method, arc discharge method, hydride vapor phase epitaxy method, molecular beam epitaxy method and so on. Then, the effects of temperature, source, atmosphere, growth time and catalysts on the morphology and crystal quality of AlN nanostructures have been summarized and analyzed systematically, as well as the growth mechanism. Finally, the physical properties of AlN nanostructures are presented and discussed in detail.