Hugoniot curves for several polymeric materials in the stress region of 0.5 GPa are measured by two methods developed for this purpose. High-speed photography or in-material gauge method is used combined with new prism technique based on the principle of total internal reflection. We measured the following materials, i.e., polymethylmethacrylate (PMMA), three kinds of polyethylene (PE specimens), polytetrafluoroethylene (PTFE), nylon 6 (N6), polycarbonate (PC), polypropylene (PP), polyvinylchloride (PVC). All of the Hugoniot curves are found to be nonlinear. In particular, three kinds of PE specimens are measured in detail, which have the different density, crystallinity, molecular weight distribution and manufacturing process. It is found that these PE specimens have different Hugoniot curves, but qualitatively similar.