The future of warfare is expected to shift towards localised regional conflicts, with the aim of minimising casualties and adapting quickly to rapidly changing battlefield conditions. Rotary-wing unmanned aerial vehicles (UAVs) are gradually becoming a highly regarded emerging force in military equipment. Their characteristics, such as ease of operation, low cost and stealthy tracking capabilities, enable them to perform outstandingly in localised conflicts. This paper provides an overview of the origin and development of rotary-wing UAVs, introduces the current development status of such UAVs domestically and internationally, and analyses their performance characteristics such as range and payload capacity. It also summarises the development trends of rotary-wing UAVs in autonomy and intelligence, persistent operations, networking and integrated operations by combining the recent practical application of rotary-wing UAVs in military conflicts. This study not only highlights the core position of rotary-wing UAVs in modern warfare, but also provides a reference for the subsequent research and development of UAVs.