The invention discloses an adjustable light source support, which comprises a lower fixing ring. The lower fixing ring is connected with an upper fixing ring through telescopic rods I; the upper fixing ring is connected with an adjusting ring through telescopic rods II; a fixing tile is fixedly arranged in the adjusting ring; the lower end of the fixing tile is connected with the upper end of a reflecting cover; the lower end of the reflecting cover is connected with the lower fixing ring; the adjusting ring is connected with a fixing table through support pillars; the lower surface of the fixing table is connected with a lamp installation seat through a telescopic rod III; a lens is arranged at the bottom part of the reflecting cover; the lens and the lower fixing ring are fixedly arranged; input ends of the telescopic rods I, the telescopic rods II and the telescopic rod III are electrically connected with an output end of a PLC (Programmable Logic Controller); and an input end of the PLC is electrically connected with an output end of an external power supply. The adjustable light source support is simple in structure, stable in performance, and convenient to maintain.