<p>Uncrewed aerial vehicles (UAVs), commonly known as drones, have gained significant popularity in landslide research due to their operational flexibility, near real-time planning capabilities, cost-effectiveness, high-resolution data outputs, and enhanced safety. This review aims to provide an analysis of UAV-based landslide investigation methodologies and their applications. It begins with an examination of UAV platforms and UAV-equipped sensors employed in landslide research, evaluating their advantages and limitations to guide appropriate platform and sensor selection. The review then explores UAV applications across three primary landslide investigation domains: landslide mapping, landslide monitoring, and landslide hazard assessment, highlighting some representative achievements in each domain. While most UAV applications focus on landslide mapping and monitoring, the use of UAVs for landslide hazard assessment remains limited. A workflow for implementing UAVs in landslide investigations is presented to offer practical guidance, followed by a discussion of regulation consideration, current challenges, and future perspectives in this field. Ultimately, the goal is to promote further advancements in UAV applications for investigating and mitigating landslide hazards.</p>