Ground-Based Augmentation System (GBAS) is steadily advancing worldwide and is expected to become the core of future aviation navigation systems. Among its components, determining the location of GBAS ground stations plays a decisive role in the implementation and formal operation of the entire system. However, there is currently a lack of efficient and flexibly deployable GBAS site selection equipment. Therefore, a portable GBAS site selection device is proposed, which mainly introduces the device's composition, working principle, functionality, and implementation evaluation methods. The provides an effective solution for rational GBAS site selection and helps promote the application and development of GBAS in the field of aviation navigation. Taking the Category I GBAS as an example, the study conducted field measurements, comprehensive analysis, and evaluation of preliminary GBAS site selection locations at a certain airport using the device, providing essential technical conditions for the operation of the GBAS system.