Abstract: Through the joint optimization of electronic scanning and platform mobility, the performance boundaries of traditional detection and communication technologies are significantly expanded by the unmanned aerial vehicle phased array system. First, the basic designs of phased array antennas for unmanned aerial vehicle platforms are classified in this paper, including element selection and array configuration, and the fundamental principles for the design of phased array antennas on unmanned aerial vehicle platforms are summarized. Then, by considering the requirements for performance parameters such as bandwidth, scanning angle, and beamwidth in application scenarios like radar detection and communication coverage, as well as the constraints on installation location, profile, and weight imposed by unmanned aerial vehicle platforms, the key technical challenges in phased array antenna design are focused on. Those challenges include core issues such as conformal technology, wideband and wide-angle scanning technology, low-cost and lightweight technology, and beamforming technology. Finally, the application prospects and development trends of phased array antennas for unmanned aerial vehicle platforms in the fields of communication and radar detection are prospected, aiming to provide valuable insights for the design and application of phased array antennas on unmanned aerial vehicle platforms.