Micro　Stereovision　based　on　a　stereo　light　microscope　(SLM)　is　used　in　micro-domains　such　as　MEMS,　micromanipulation,　microassembly　et　al.　SLM　is　an　important　device　obtaining　images　of　micro　objects　and　play　an　important　role　in　auto　micro-navigation,　auto　micro-position,　micromeasurement　et　al.　Definition　of　the　imaging　model　for　a　SLM　differs　from　the　imaging　model　of　a　normal　optical　microscope　in　the　following　aspects:　(1)　The　vision　principle　of　SLM　uses　the　same　principle　with　binocular　Stereovision.　For　obtaining　depth　information　of　the　object　space,　the　stereoscopic　imaging　model　of　SLM　needs　image　data　from　matching　of　stereo　images.　(2)　There　is　correlation　between　the　two　optical　paths　of　SLM.　This　indicates　that　a　stereoscopic　imaging　model　of　SLM　is　nonlinear.　(3)　A　stereoscopic　imaging　model　of　SLM　has　its　unique　calibration　parameters　differing　from　parameters　of　other　optical　systems.　In　this　paper,　a　stereoscopic　imaging　model　of　SLM　is　constructed.　The　symmetry　and　the　differences　between　the　two　optical　paths　of　SLM　are　used　to　calibrate　the　main　parameters　and　the　rectification　parameters　of　an　imaging　model.　Through　experiments,　we　analyze　the　robustness　and　dependency　of　parameters　under　different　magnification　of　the　objective　lens.　©　2005　IEEE.