A cylindrical lens working in the terahertz (THz) frequency range is designed and its sample is also fabricated by using the three-dimensional (3D) printing technique. A test on this sample is conducted. The comparison among the testing results, the simulation results, and the testing results of the commercial THz lenses is made. The results show that the focal lengths of two kinds of lenses are both about 100 mm, which matches with the simulation results. Moreover, under different propagation distances, the full widths at half maximum of spots for the printed lenses are very close to those for the commercial lenses, which proves that the 3D printing technique can be used in the fabrication of THz optical devices, such as cylindrical lenses.