Owing to unique electromagnetic properties and support of surface plasmon polariton at terahertz frequency, graphene has gained momentum for the realization of the graphene plasmonic THz antenna. The appropriate selection of substrate for graphene THz antennas can provide an effective performance to the antenna. In this paper, we investigated the performance of graphene THz antennas over silicon-based substrates such as silicon, silicon dioxide, silicon nitride , and silicon carbide in order to study the impact of silicon-based substrates on graphene THz antennas. Antennas are analyzed in terms of the reflection coefficient, resonant frequency , impedance bandwidth , radiation pattern, half-power beamwidth, front to back ratio, and directivity . The proposed graphene THz antennas over silicon-based substrates will be promising for THz short-range communication, sensing, and biomedical application. • Graphene THz antennas using different silicon based substrates such as Si, SiO 2 , Si 3 N 4 , and SiC are presented in this work. • Antennas are analyzed in terms of the reflection coefficient, resonant frequency, HPBW, F/B ratio and directivity. • It has been found that all silicon based substrates are suitable candidates for graphene THz antennas. • The graphene antennas over silicon based substrates will be promising for biomedical, communication and sensing application.