The invention discloses an adjustable light source bracket, comprising a lower fixing ring, the lower fixing ring is connected to the upper fixing ring through the first telescopic rod, the upper fixing ring is connected to the adjustment ring through the second telescopic rod, and the inside of the adjustment ring Fixedly install the fixed tile, the lower end of the fixed tile is connected with the upper end of the reflector, the lower end of the reflector is connected with the lower fixing ring, the adjusting ring is connected with the fixed platform through the pillar, and the lower surface of the fixed platform is connected by a telescopic rod three Connected to the lamp mounting base, the bottom of the reflector is provided with a lens, the lens is fixedly installed with the lower fixing ring, and the input ends of the first telescopic rod, the second telescopic rod and the third telescopic rod are all electrically connected to the output end of the PLC controller , the input end of the PLC controller is electrically connected to the output end of the external power supply. The adjustable light source support has a simple structure, stable performance, and is easy to maintain.