In this paper, bio-polyamides were synthesized by melt polycondensation. Three layers of silver-loaded polylactic acid (PLA)/ bio-based polyamide（BDI）/polylactic acid（PLA）fiber membranes were prepared by electrospinning. Structures and properties of the membranes were characterized in detail by water-contact angle, TG thermogravimetry, scanning electron microscopy toxicity, in vitro degradation and antibacterial test. The results show that, the morphologies of the silver-loaded PLA/BDI/PLA fiber membranes are good. The PLA layer, as skeleton material, makes the BDI layer inaccessible to water and improves the dimensional stability of the membranes. The fiber membranes have a good biocompatibility and bacteriostasis. The addition of silver ions does not affect the thermal stability of the polymers themselves, and has little effect on the degradation of the fiber membranes, but can prolong the antibacterial durability of the fiber membranes.