By using the template of electrospun polyacrylonitrile(PAN) nanofibers,PANI/PAN nanofibers of conducting forms were prepared in situ chemical polymerization of aniline with the oxidant(NH4)2S2O4.The SEM indicates that the long nanofibers are randomly distributed in a fibrous mat with a rough surface composed PANI particles whose diameters are about 70-80 nm.And the nanofibers′ core-shell structure,i.e.coaxial structure,which is consisted of core nanofiber of PAN and shell of PANI,is also displayed clearly by TEM image.The PANI/PAN coaxial conducting nanofibers were dedoped by dilute ammonia solution and then redoped by PFOS,exhibiting wonderful superhydrophobicity.The wettability of PANI/PAN coaxial nanofiber can be actively controlled by the doped different organic sulfonic acids on the surface.