SBAS(Satellite Based Augmentation System) provides GNSS satellite orbit and clock corrections for positioning accuracy improvement of GNSS users. In this paper, the accuracy of SBAS satellite orbit and clock corrections were analyzed by comparing with the IGS(International GNSS Service) precise ephemeris. The GPS antenna phase center offsets and the P1-C1 bias are considered for the analysis. The correction data of the US WAAS and the Japanese MSAS were analyzed. The analysis results showed that the SBAS satellite orbit and clock corrections are highly correlated. The correction data accuracy depends on the SBAS ground network size and orbit trajectories.