Two unique laser processes of 'PLA in low vacuum (PLALV)' and 'PLA in liquid (PLAL)' have been examined to fabricate FePt nanoparticles and the magnetic and structural properties were investigated. The particles as prepared by PLALV showed a superparamagnetic behavior with an fcc structure. The annealing temperature dependence of the transformation from fcc to fct structure was studied by the structural and magnetic properties. A large coercivity of 3.6 kOe at 300 K was obtained by the low temperature (500 C) annealing. Composition deviation due to Fe dissolution in PLAL process was successfully suppressed by Ar bubbling.