The work presents the results of the formation and structural properties study of aluminum nitride (AlN) nanostructures on the hexagonal boron nitride (h-BN) flakes transferred onto a silicon dioxide/silicon (SiO2/Si) substrate. For the first time, the possibility of aluminum nitride nanowire growth on h-BN flakes using plasma-assisted molecular beam epitaxy through a self-induced mechanism is demonstrated. The experimental dependence of the length of synthesized nanowires on their diameter is provided. The dependence corresponds to an analytical solution of the length versus diameter for nanowires grown by a self-induced mechanism. Raman spectroscopy studies reveal the wurtzite crystal phase of the aluminum nitride nanowires formed on h-BN flakes. The full width at half maximum of the E2(high) peak is 5 cm-1, suggesting high crystalline quality of nanowires. These results have implications for the development of deep-ultraviolet optoelectronic devices and the advancement of III-nitride optoelectronics integrated with silicon technology.