As the absorption of terahertz (THz) waves is very sensitive to the concentration of water molecules, they have great potential in bioimaging. Polarimetric imaging techniques have been successfully employed to retrieve fine details of a material or to help resolve the orientation of structures in the sensing sample at microwave and optical frequencies. In contrast, little work has been reported at THz band. In this paper, we present our recent effort in building a 0.3 THz polarimetric imaging system for taking both reflection and transmission imaging experiments. The experience gained in this work paves the way for bioimaging of tissues and cells at higher THz frequency bands.