The structural, electronic, vibrational and magnetic properties of a novel C48N12 aza-fullerene are studied by using density functional and Hartree-Fock methods. Optimized geometries and total energy of this aza-fullerene are calculated. The HOMO-LUMO gap Of C48N12 is found to be about 1 eV smaller than that Of C-60. Fifty-eight IR-active frequencies and 10 NMR spectral signals are predicted for C48N12. Diamagnetic shielding factor, polarizability and hyperpolarizability Of C48N12 are calculated. Our results suggest that C48N12 may have potential applications as semiconductor components and possible building materials for nanometer electronics, photonic devices and diamagnetic superconductors. (C) 2002 Elsevier Science B.V. All rights reserved.