Amine-functionalized poly(lactic acid) (PLA) nanofibers were prepared by co-electrospinning of PLA and aminopropyltriethoxysilane(KH550) in 1,1,1,3,3,3-hexafluoroisopropanol. The contents of amine groups on the surfaces of the fibers were measured by chemical titration. The results show 19%-26% of total amine groups appeared on the fiber surfaces when 3%-13% of KH550 to PLA is added. The amine-functionalized PLA nanofibers were also characterized by field emission scanning electron microscopy, differential scanning calorimetry(DSC), contact angle measurements and uniaxial tensile tests. It has been shown that the addition of KH550 can introduce amine groups on PLA fiber surfaces, meantime the fiber diameter decreases, T-g of PLA increases, T-m. of PLA decreases, the hydrophilicity of the fiber mat slightly increases and its mechanical properties decreases. Au nanoparticles were adsorbed on the surface of amine-functionalized PLA nanofibers, which showed good catalytic activity and reusability for the reduction of 4-nitrophenol.