Using the potassium persulfate( KPS) as an initiator,through modified reaction of diacetone acrylamide( DAA) and sodium alginate( SA),the amphiphilic SA-PDAA block copolymer was synthesized. By electrospinning the mixture of SA-PDAA and polyvinyl alcohol( PVA) solution,SA-PDAA / PVA electrospun fibers were prepared. The structure and properties of SA-PDAA were characterized by means of Fourier transform infrared spectroscopy( FTIR),differential scanning calorimetry( DSC) and fluorescence spectrum. Furthermore. The physical properties of SA-PDAA spinning solution were determined by viscometer,surface tensiometer and electrical conductivity meter,the morphology of SA-PDAAA / PVA electrospun fibers were determined by scanning electron microscopy( SEM). And the drug release studies of SA-PDAAA / PVA electrospun fibers were also investigated. Experimental results showed that DAA had successfully grafted onto the sodium alginate molecular chains. The critical aggregation concentration measured by fluorescence spectrum was reduced to 0. 072 g / L,which demonstrated the good amphipathy of SA-PDAA. The morphology of SA-PDAA /PVA electrospun fiber exhibited more uniform size. The drug release properties show that SA-PDAA can effectively slow the drug release rate,thus improving the retarded releasing characteristics of SA-PDAA / PVA electrospun fibers.