The photonic lattice induced by nondiffracting discrete beam was observed in an externally biased cerium doped strontium barium niobate(SBN) photorefractive crystal. And the photonic lattice induced by the interference of three beams and six beams was observed especially. Some differences and similarities of the photonic lattice in these two cases were analyzed by far-field diffraction pattern, Brillouin-zone spectroscopy and Fourier spatial spectrum. And some theoretical analysis were carried out. The results show that the photonic lattice induced by the interference of three beams is more uniform and stable. In addition, the transmission diagrams of the photonic lattice induced by the interference of four beams, five beams, seven beams, eight beams, nine beams and ten beams were simulated respectively.