Two-dimensional dodecagonal boron nitride is designed via first principles calculations. Calculations unveil that the proposed two-dimensional dodecagonal boron nitride is energetically stable and less dense than what is observed with hexagonal and octagonal configurations of two-dimensional boron nitride. Furthermore, it is found that modifying the atomic configuration of two-dimensional boron nitride can tune the band structure. In particular, a direct bandgap of 5.2 eV is observed for two-dimensional dodecagonal boron nitride while a direct bandgap of 5.79 eV and an indirect bandgap of 5.20 eV are observed for the hexagonal and octagonal configurations, respectively. Thus, tailoring atomic configurations demonstrates the possibility to tune the electric band structures of two-dimensional materials.