The feasibility and widespread commercialization of 5G technology in coming years has been already ensured by the recent success of trials across the world. The spectrum allocated for 5G networks is sub-6 GHz and millimeter wave (24.25–86 GHz), which will provide the ten times faster data rate than 4G. However, the dramatic growth in new applications such as autonomous driving, machine connectivity, and wireless backhaul will demand higher data rate with lower latency as compared to 5G. The escalating demands for the higher data rate attract the researchers to think toward new frequency range for future communication maybe beyond 5G or 6G. To achieve the higher data speed, the bandwidth must be higher. The expected 6G data rate is 0.1–1 Terabits per second (Tbps) is possible when one will move in terahertz (THz) frequency regime. Even undefined, the unexplored low-THz regime (100 GHz to 1 THz) is one of the potential candidates for the future communication due to congestion in millimeter and optical region. The shift of carrier frequency in THz regime helps to improve bandwidth and hence data speed; however, this will impose the difficulties like higher atmospheric losses as well as manufacturing problems due to very small-sized communication devices. The THz antenna is most imperative device in wireless communication technology, which is the part of transmission as well as reception of the signals. The atmospheric attenuation at low-THz frequencies needs the design of higher gain antennas, and the size constraint requires the use of a different technology or materials to implement the THz compatible antennas. Although 5G technology has not completely implemented yet, the researchers are working toward theses antennas since last decade. The key goal of this review paper is to summarize the overview of available literature on THz antennas for beyond 5G or 6G communication. The need of THz communication and the challenges or technical issues for implementation is discussed in Introduction section. In the next section, some recent THz antenna designs are summarized, which may be possible candidates for the future communication followed by the conclusion.