The plane wave method is developed for calculating photonic band structure in chiral medium, at this basis, the photonic band structure of simple cubic lattice made of chiral medium is calculated. Results show that cutoff frequencies below which there are no propagating modes appear in both of two kinds scc lattices which are the array of “chiral spherical atoms” in dielectric material and the array of “dielectric spherical atoms” in chiral matrix. There is a cutoff grequency below which there are no propagating modes. The potential application of the photonic lattice is discussed.