Iron (Fe) nanoparticles coated with boron nitride (BN) nanomaterials were synthesized by using Fe(4)N and B powders as raw materials. The Fe(4)N was reduced to alpha-Fe during annealing at 1000 degrees C for several hours with flowing 100 sccm N(2) gas. The reaction was predicted by Ellingham diagram. The atomic structure and magnetic properties were investigated by high-resolution electron microscopy and vibrating sample magnetometer system.