Abstract: The traditional illumination model divides the reflection of a surface into two parts: specular term and diffuse term. The diffuse term is calculated by the Lambert cosine law. As the biological tissues are full of water, they not only have features of deterministic media but also have features of random media. In order to simulate the biomedical surface realistically. Its surface reflection and scattering of the incident light should be taken into account. An attempt is made to calculate the diffuse reflection by solving the transport equation under the single scattering case. The details of volume data are regarded as the texture and both the anisotropic scattering and specular reflection are accounted for. Satisfactory result is shown at the end of the paper.