A new technique forsurface modification of polymer fibers is introduced by irradiating with UV excimer laser,this technique can be used to modify the chemical and physical properties of fiberssurface. Under certain conditions the irradiation of polymer fibers induced acharacteristic morphology on the polymer fiber surface. The original smooth surface ofpolymer fibers changes its morphology to a rather regular roll-like structureperpendicular to the fiber axis after this treatment. The dependence of characteristicsurface data on laser fluency and pulse number is studied. The mechanism for formationperiodic surface is also discussed.