As shown, the bulk vertical ionotronic nanostructures can be fabricated by using introduction of the ionic RbNO$_3$ salt melt between the (0001) layers of InSe crystal. The chemical composition and morphology of these structures are investigated by x-ray electron spectroscopy and atomic force microscopy. As determined, they consist of the ultrathin 2$D$ InSe layers separated by solid layers of ‘ion salt–In$_2$O$_3$’ electrolyte. During the self-organization process of such structures at temperatures of the melt, which exceed the temperature of the RbNO$_3$ decomposition onto nitrides and nitrates, the ‘ion salt–InSe’ heteroboundaries are oxidized, and nanostructures with high ionic conductivity are formed. They have the form of nanosize rings and are characterized by high lateral density $\sim 10^{9}–10^{10}$ сm$^{-2}$. As established, these nanostructures are grown in the (0001)InSe planes, which are arranged periodically at a distance of about tens nm along the crystallographic axis $C$.