. The accurate first-principle method was used to calculate the electronic structures of the four boride superconductors. Their DOS (the density of states), band structures as well as their specific electronic structures were discovered. It was found that they all had a metallic band crossing the Fermi surface on the Γ point. These characters made their attribute of superconductivity and the interstics of NbB was the least which resulted in its higher Tc than the others.