Abstract: The quality of navigation satellite observation data is a direct factor that affects the positioning accuracy of ground augmentation system. The number of satellite observations obtained by BeiDou ground-based augmentation system after the adaptive transformation of Beidou-3 Navigation Satellite System (BDS-3) has increased by 30%−50% compared with the original Beidou-2 Navigation Satellite System (BDS-2). It is very important to evaluate and analyze the quality of these observations. In this paper, we propose a method to evaluate the quality of observation values of reference stations, such as analytical data integrity and multipath error, and use two methods such as zero-base line test and precise single point positioning test, to integrate the BDS-3 data analysis method of regional ground augmentation system. Based on this method, an empirical test was conducted in the study area. The results show that the data quality of BDS-3 satellites in the Asia-Pacific region has reached the same level as that of GPS. Due to the better spatial distribution structure of BDS-3 satellites, the available observation value of high elevation angle (altitude angle >50°) obtained by the ground stations has increased more than 200% compared with that of single GPS system.