Phosphorus is an important element required for plant growth. The absorption and transportation of Pi are carried out by phosphate transporter in legumes. In this paper,phosphate transporter AsPT6,a new member of pht1 family,was identified in Astragalus sinicus. AsPT6 was expressed in leaves,stems and roots. The expression of AsPT6 was increased significantly in the roots and nodules when inoculated with Mesorhizobium huakuii 7653R. The results of tissue localization showed that AsPT6 was expressed in the vascular tissue of roots,nodules,and the junctions between root and nodule,indicating that AsPT6 may play a role in transporting phosphate from the root to nodule. Overexpression and RNA silence of AsPT6 significantly affected the nodulation and nitrogenase activity of nodules. It is indicated that AsPT6 is involved in the transportation of phosphorus during the formation and development of nodules.