Bismuth-based ferroelectric ceramics are currently under intense investigation for the potential as Pb-free alternatives to lead zirconate titanate-based (Pb(Zr,Ti)O3-based) piezoelectrics. In this work, first-principle calculations were performed for the electronic structures of sodium bismuth titanate (Bi0.5Na0.5TiO3) materials with all possible crystal symmetries, including rhombohedral, monoclinic, tetragonal, and rhombohedral. We expected that our works could help further understand the role of phase transition in lead-free ferroelectric Bi0.5Na0.5TiO3 materials.