The invention discloses an LED lamp strip cutting device. The LED lamp strip cutting device comprises a workbench, and the two sides of the bottom of the workbench are fixedly connected with supporting legs. The bottoms of the supporting legs are fixedly connected with a bottom plate. The two sides of the top of the workbench are fixedly connected with supporting plates, and the tops of the supporting plates are fixedly connected with a cross plate. A conveying roller is movably connected between the two supporting plates through a rotary shaft, and the top of the conveying roller is movably connected with a lamp strip body. One side of each supporting plate is fixedly connected with a conveying motor. According to the LED lamp strip cutting device, by arranging the supporting plates, thecross plate, the conveying roller, a conveying motor, a movable hole, a movable plate, a cutting motor, cutting discs, a tooth plate, a sliding plate, a transmission motor and a gear, the distance between the two cutting discs can be correspondingly adjusted according to needs, and the adjusting process is easy to operate; and use is convenient, the production efficiency of LED lamps is improved,and then great economic benefits are brought to LED lamp processing enterprises.