Abstract: The low-altitude economy has gained significant attraction in recent years, particularly in the context of smart agriculture. It is very necessary for innovative solutions to enhance agricultural productivity and sustainability, due to the more pressing populations and scarce arable land. The low-altitude economy can be expected to offer a promising avenue for these challenges. This review was focused on the frontiers and hotspots in the agricultural application of the low-altitude economy in rural areas. A literature analysis was employed to analyze the journal articles and global patents from 2000 to 2024. The keyword co-occurrence networks and citation relationships were determined to identify the research hotspots and directions. Low-altitude technologies (particularly unmanned aerial vehicles, UAVs) also shared key applications in agricultural information acquisition, plant protection, land resource management, environmental monitoring, and rural logistics. The UAVs equipped with the advanced sensors were used to collect real-time data on crop health and growth, soil conditions, and weather patterns, in order to optimize irrigation, fertilization, and pest control. Precision spraying also reduced the chemical usage. While the land resource management benefited from the accurate monitoring. Environmental and disaster monitoring with UAVs also enabled swift responses to floods, droughts, and wildfires. Additionally, the UAVs also transformed into agricultural logistics, particularly for the efficient transport solutions in remote areas. Several technological challenges were given to fully realize the immense potential of the low-altitude economy. One of the primary challenges was to specially design advanced UAVs in diverse and harsh agricultural environments. The better performance was required for the flight stability, battery life, and payload capacity. Flight control systems were also required for safe and efficient operations in the crowded airspaces. The data accuracy and reliability were further enhanced to refine the onboard mission payloads and auxiliary equipment, such as the high-resolution cameras and multispectral sensors. Information perception and precision operation were critical to real-time data processing and decision-making. The air-ground collaborative control systems were essential to integrate the low-altitude operations with the existing agricultural infrastructure. The successful implementation of the low-altitude economy in agriculture was dependent heavily on the decision-making on the regulatory frameworks. Furthermore, the legal systems and industry standards were established to manage the low-altitude airspace for safety, efficiency, and accountability in Europe and the United States. These frameworks also provided valuable implications for other countries and regions, including China. Fine-grained management was selected to promote the pilot of low-altitude airspace opening in smart agriculture; Streamline certification was also utilized to optimize the airworthiness approval procedures for the low-altitude aircraft; Regional low-altitude economy was also enhanced to construct the industrial clustering and the testing bases. Future research can be focused on lightweight sensors and intelligent algorithms. An "air-space-ground" monitoring network can be expected to integrate and optimize the dynamic airspace. Further applications can also be expanded into carbon sink monitoring, biological breeding, and disaster emergency response. This finding can provide theoretical and practical references to accelerate the low-altitude economy in rural areas. The great contribution can also be gained to the agricultural modernization and rural revitalization.