First time, polyacrylonitrile (PAN)/Ag2CO3 composite nanofibers (NFs) with uniformly distributed Ag2CO3 nanoparticles (NPs) inside polyacrylonitrile NFs were fabricated via simple and versatile technique; electrospinning of colloidal solution of PAN and Ag2CO3 NPs. In this work, Ag2CO3 NPs were synthesized by ion-exchange method between Ag(NH3) (2) (+) and NaHCO3. The experimental result demonstrated that PAN/Ag2CO3 composite NFs with average diameter of approximately 430 nm can exhibit good photocatalytic activity for the photodegradation of methyl red under visible light irradiation. In addition, thus obtained composite NFs displayed enhanced antibacterial activities toward both gram-positive and gram-negative bacteria due to its photogenerated electron-hole pairs indicating that this sort of material may represent a new, promising alternative with a wide range of potential application in the field of water treatment.