Various nanostructured TiN(001)/MgO(001) superlattices based on a repeated slab model have been investigated by using the total energy pseudopotential method [1][2]. As a result of the structural relaxation, the electronic states of the rectangular TiN dot/MgO(001)-2x2 and 3x3 superlattices are semiconducting. Their band gap values are 0.18 eV (2x2) and 0.54 eV (3x3) in the DFT-LDA calculation. All the calculated electronic states of rectangular parallelepiped TiN dot/MgO substrates are metallic. Their electronic properties depend on a shape of the TiN dot and a size of the MgO substrate.