A method and system to measure and image the full optical scattering properties by inverse spectroscopic optical coherence tomography (ISOCT) is disclosed. Tissue is modeled as a medium with continuous refractive index (RI) fluctuation and such a fluctuation is described by the RI correlation functions. By measuring optical quantities of tissue (including the scattering power of the OCT spectrum, the reflection albedo α defined as the ratio of scattering coefficient μs, and the backscattering coefficient μb), the RI correlation function can be inversely deduced and the full set of optical scattering properties can be obtained.