Disclosed is a streetlight having a xenon lamp in that a lamp assembly having a xenon lamp is formed at the existed streetlight, whereby lowering a power consumption and remarkably increasing the period of the lamp change. The present invention is to provide a streetlight having a xenon lamp in that the xenon lamp is formed therein, whereby emitting a lot brighter light with low power consumption. Also, the present invention is to provide a streetlight having a xenon lamp in that a ballast is built in a lamp assembly having the xenon lamp, so that the change of the xenon lamp can be easily performed and the lamp assembly can be easily applied to even the existed streetlight. Moreover, the present invention is to provide a streetlight having a xenon lamp in that a plurality of xenon lamps can be formed at one lamp assembly and the number of each lamp can be controlled, thereby adjusting the brightness thereof and another xenon lamp and ballast can be operated during the damage of the operating xenon lamp, thereby remarkably increasing the period of the lamp change.