If we can apply the diffuse equation to analyze and decide optical properties of superficial biological tissue, we can determine if the pathological changes occur in vivo, thus we can realize the noninvasive in vivo measurement. Currently, a semi-infinite media photon migration model and a two-layered turbid medium model are utilized widely. But actually, there is a multi-layered turbid medium in tissue. According to the diffusion equation, employing the extrapolated boundary condition, we analyze the diffusion of photons of a three-layered matched medium and deduce the solution of Green's function. Through comparing the spatially resolved reflectance between the solution of three-layered matched media diffusion equation and Monte-Carlo simulation, we find our solution of a three layered matched media theory not only accords with a two-layered turbid medium model which is solved by A. Kienle, but also agrees with Monte-Carlo simulation.