The invention discloses a small distortion large vision field stereo endoscope object lens structure. The small distortion large vision field stereo endoscope object lens structure comprises a direct vision endoscope and a strabismus endoscope, wherein the direct vision endoscope sequentially comprises protection glass, a first negative lens, a second negative lens, a parallel flat board, a flat convex lens and a subsequent glued lens group along a light spreading direction, and the strabismus endoscope sequentially comprises protection glass, a first negative lens, a second negative lens, a parallel flat board, a turning prism, a flat convex lens and a subsequent glued lens group along the light spreading direction. The small distortion large vision field stereo endoscope object lens structure has an ingenious structure, the two negative lenses are in front of a diaphragm, the first negative lens is a flat concave negative lens, the second negative lens is a convex concave negative lens, the two negative lenses are organically combined, system distortion can be corrected through optimization design, so large vision field small distortion endoscope optics systems can be designed out, the first negative lens and the second negative lens are respectively glued to the parallel flat board, the technology is good, positioning precision is high, the sealing technology is improved, and assembly and adjustment cost is reduced.