Dueto diffuse nature of lightphotons, Diffuse Optical Tomography (DOT) image reconstruction is a challenging 3D problem with a relatively large number of unknowns and limited measurements. AS a result, the computational complexity of the existing DOT image reconstruction algorithms remains prohibitive. In this work, we investigate an adaptive multigrid approach to improve the computational efficiency and the quantitative accuracy of DOT image reconstruction. The key idea is based on locally refined grid structure for region of interest (ROW The ROI may be defined as diagnostically significant regions, strong background heterogeneities andlor deep optical edges. A 2-level mesh is generated to provide high resolution for RO1 and sufficiently high resolution for the rest of the image. A Least Squares (LS) solution is formulated for the inverse problem. Fast Adaptive Composite (FAC) 2-Grid algorithm is employed to solve the inverse problem. Conjugate Gradient (CG)is used at the relaxation...