The invention relates to a coaxial image system applied to an LED laser cutting device, comprising a coaxial LED point light source module, a 45-degree total reflection mirror, a wide-angle CCD module, a first 45-degree spectroscope, a small-vision field high-magnification upper CCD module, a second 45-degree spectroscope, a wavelength selection mirror, an LED ring light source, a focusing lens and a small-vision field high-magnification lower CCD module; the coaxial LED point light source module, the wide-angle CCD module and the small-vision field high-magnification upper CCD module are arrayed in parallel from top to bottom, the wavelength selection mirror is mounted between the CCD module and the focusing lens, the LED ring light source clings to the focusing lens which faces directly towards a workpiece, the small-vision field high-magnification lower CCD module is mounted below the workpiece. The invention realizes coaxial real-time image positioning function in the LED laser cutting device, combined usage of the wide-angle CCD and the small-vision field high-magnification upper CCD realizes micrometer-grade measurement accuracy, and the convenient switch of the small-vision field high-magnification upper CCD and the small-vision field high-magnification lower CCD meets the demands of front-cutting, back-cutting, surface coarsening and the cutting of back-aluminized wafer.