Diffusion　optical　tomography　in　a　heterogeneous　turbid　medium　with　the　use　of　frequency-domain　is　in　research,　as　it　can　provide　the　great　significance　optical　parameters　used　to　reconstruct　and　then　we　can　obtain　the　new　physiological　information　about　biological　tissue　function　and　pathological　transformation.　In　this　paper,　we　introduce　a　simulation　for　the　system　of　near-infrared　diffusion　optical　tomography,　and　in　the　system　we　can　simulate　the　propagation　characteristics　of　light　in　tissue.　In　the　traditional　tissue　boundaries　scheme,　the　detectors　are　equal　distribution,　but　some　of　detectors　are　small　role　in　tissue　reconstruction,　so　in　this　paper,　we　discuss　the　optimization　problem　of　the　number　and　placement　for　detectors,　which　has　been　confirmed　and　verified　in　simulation.　The　simulation　results　indicate　that　about　eight　detectors　and　the　opposite　position　of　source　can　provide　a　more　accurate　reconstruction　of　tissue　optical　parameters　with　high　spatial　resolution　and　less　time.　©　2012　Huazhong　Univ　of　Sci　&　Tec.