The invention, which belongs to the field of optical imaging technology, relates to a visible near-infrared spectrum imaging system and method so that visible near-infrared wide-spectrum multi-spectral imaging can be realized, axial and vertical chromatic aberration can be eliminated, and the good imaging quality can be realized. The system is composed of a lens assembly, a filter assembly, a focusing compensation assembly and a detector focal plane that are arranged in sequence. The lens assembly includes a first mirror, a diaphragm, a second mirror, a third mirror and a fourth mirror; the first mirror is a meniscus mirror with a weak negative focal power; the second mirror is a convex lens; the third mirror is a concave lens; and the fourth mirror is a convex lens. The lens assembly focuses incident light; the light enters the filter assembly; the filter assembly filters light beyond the waveband; the light enters the focusing compensation assembly; and then the light is focused at the detector focal plane. The distance between the lens assembly and the detector focal plane is fixed; and clear target imaging at different distances is realized by changing light modulation compensation mirrors with different thicknesses.