Polymeric fibers with nanometer-scale diameters are produced by electrospinning method. When the electrical forces at the surface of a polymer solution or melt overcome the surface tension, then electrospinning occurs and nanofibers are made. Polyethylene oxide(PEO) have been electrospun in our laboratory Electrospun PEO fibers are observed by scanning electron microscopy or transmission electron microscopy In thl:; study. the average diameter of the electrospun fibers decreases with decreasing PEO concentration and increasing electric field strength. The optimal conditions for producing uniform PEO 100nm fibers are the 10wt% PEO concentration at a voltage 25 to 30kV and a distance of 10cm from tip to collector.