Photonic crystals are materials with regular periodicity of dielectric structures,which can create a range of forbidden frequencies called photonic bandgap.Photons with energies lying in the bandgap cannot propagate through the medium.Moreover,photonic crystals have the ability to manipulate,confine and control light,thus provide the opportunities to shape and mould the flow of light for photonic communication technology and photonic computer.In present,the preparation of photonic crystals,especially those in visible or near-infrared region,is the key to the development of photonic crystals.In this paper,the conception and characteristics of photonic crystal are described at first,and then the research in experiment and application are introduced respectively.In experiment research,fabrication method of photonic crystals is depicted.In application,single-mode light-emitting diode,optical waveguide device and microwave antenna are described.