FePt thin films are exposed to pulsed energetic H+ ion beam from plasma focus. in irradiated films, the phase transition from the low K-u disordered face-centered-cubic structure to high K-u ordered face-centered-tetragonal phase was achieved at 400 degrees C with the order parameter S ranging from 0.73 to 0.83, high coercivity of about 5356 kA/m, high negative nucleation field of about 7700 kA/m and high squareness ratio ranging from 0.73 to 0.79. The advantage of using plasma focus device is that it can lower phase transition temperature and significantly enhance the magnetic properties by a pulsed single shot exposure. (C) 2008 Published by Elsevier B.V.