A number of distributed Bragg reflectors (DBRs) based on AlxGa1 - xN /GaN quarterwave layers with vari－ousAl content have been grown on (0001) sapphire substrates using high quality GaN buffers bymetalorganic chemi－ cal vapor deposition (MOCVD). XRD,AFM, SEM and reflectance measurement are emp loyed to analyze the structure quality, thickness and surface morphology of AlxGa1 - xN /GaN DBRs.