Satellite Based Augmentation System (SBAS) is an important part of Beidou System (BDS). First of all, the basiccomposition of BDS SBAS is introduced. Then, the complete and correlation algorithm is introduced. Finally, the experiment ofpositioning accuracy of BDS SBAS using anti-interference antenna which with and without interference is done. The result showsthat the positioning accuracy of BDS SBAS is obviously better than positioning.