Many biological tissues consist of fibril structures. The scattered light of tissues provides abundant information about the properties of tissues. The polarization property of scattered light can reveal structure and type of tissue. Understanding the propagation property of polarirzed light in scattering medium is helpful to improve imaging gating method and diagnosis technology. In this paper, the transmitted light from a section of dentin was measured. A linearly polarized He-Ne laser beam was incident on the sample, and the transmitted light is recorded. The image showed anisotropic spatial distribution, indicating the light propagating along the fibers. The polarization property of the scattered light was related to the polarization direction of the incident light. A Monte Carlo simulation considering cylindrical scatterers was utilized to model the scattering property of microstructure in dentin. The experimental results are compared with the simulation. The ordered fibers have influence on the spatial distribution and the polarization state of scattered light.