The first principle calculation was employed to investigate the formation energies and structural, electronic, and magnetic properties of intrinsic and Ni-doped sodium bismuth titanate Bi0.5Na0.5TiO3(BNT). The obtained formation energies indicate that Ni atoms prefer to dope into Bi-sites in the lattice of BNT while the calculated band structure shows that the doping leads to the emergence of new midgap energy states in the bandgaps, reducing the bandgap value of doped materials.