Motivated by the need for unmanned aerial vehicle (UAV) communications in the modern era of wireless communication, this chapter focuses on a case study of millimeter‐Wave (mmWave) and teraHertz (THz) communication and the technical challenges in applying mmWave and THz frequency band for communication with UAVs. Specifically, this chapter focuses on the placement of UAVs to replace the terrestrial backhaul network with an aerial network. In addition, we address the performance of UAV‐enabled hybrid heterogeneous network (HetNet) by considering stringent communication‐related constraints, e.g. bandwidth, data rate, and signal‐to‐noise ratio (SNR). Also, the association of terrestrial small‐cell base stations (SCBs) with UAVs is addressed such that the sum rate of the overall system is maximized. To this end, an association algorithm is presented, which deals not only with the association of SCBs but also with backhaul link capacity. A detailed analysis of simulation‐based results shows a favorable performance of UAV‐assisted wireless network.