The invention discloses an easily-detachable and high-strength scaffold for mounting lighting lamps on building external walls in the technical field of construction engineering. The scaffold comprises a lower scaffold and an upper scaffold, reinforcing ribs are arranged on left and right sides of the bottom side walls of workbenches, fixing sleeves matched with support feet are arranged on left and right sides of the top of the workbench on the lower side, bolt rods are inserted in left and right side walls of the fixing sleeves in a penetrating manner, adjusting devices are arranged on the bottom side walls of the support feet on the lower side, and bottom plate devices are arranged on bottom side walls of the adjusting devices. The hinged support feet in the device can be rotated to behidden in bottoms of the workbenches, so that transportation and storage are facilitated, when sliders slide to one side close to the support feet, the support feet are kept in a vertical state, stability of the support feet is strengthened, accidental shaking is avoided, and work of the device is facilitated; the bolt rods are inserted in inner cavities of penetrating holes, the upper scaffold and the lower scaffold are more stably connected, and assembly of the device is facilitated.