Terahertz (THz) antenna is an indispensable component of the future 6G mobile communication, among which THz lens antenna has attracted extensive attention due to the merits of high gain, stable radiation performances, low cost etc. The THz lens antennas can operate without suffering from the problem of feeding occlusion, they can also realize the functions of beam control. The function of focusing can not only be applied in the imaging system, but also play the role of collimation in the test devices. The advancement of THz fabrication technology makes the THz lens antenna more precise and effective, which further promotes the development of the THz lens antenna. In this review, the THz lens antennas reported in the last five years are summarized by synthesizing their features such as functions, fabrication processes, morphologies, and applications.