A road lighting device is provided. The provided road lighting device is installed on a guard rail or a median barrier, which comprises: a lighting lamp which is installed to be adjusted in angle inside a housing to light a road; an angle-adjustable gear connected with an outer driving body installed inside the housing; a lighting housing which has a gear body engaged with the angle-adjustable gear and hinge-coupled to the lighting housing to allow pivoting, wherein the lighting lamp is mounted; and the housing which is embedded in the guard rail or the median barrier.
