Coaxial electrospinning using surfactants as sheath fluid for preparing high-quality polymer nanofibers is studied. PAN nanofibers are fabricated using this process with Triton X-100 solutions in DMF. FESEM demonstrates that the Triton X-100 solution has a significant influence on the quality of the nanofibers. The nanofiber diameters can be controlled by adjusting the concentration of Triton X-100 in the sheath fluids with a scaling law D?=?640 C-0.32. The mechanism of the influence of Triton X-100 solutions on the formation of PAN fibers is discussed and it is demonstrated that coaxial electrospinning with surfactant solution is a facile method for achieving high-quality polymer nanofibers.