Ferroeletromagnetic Pb(Fe1/2Nb1/2)O3(PFN) ceramics has been investigated systematically. Differential Scanning Calorimetric (DSC) analysis revealed that para-ferroelectric transition at about 380K and para-antiferromagnetic transition at about 145K were first order and weak first order or second order transition, respectively. Electronic Paramagnetic Resonance (EPR) indicated that above Néel temperature the resonance shows paramagnetic characters and under Néel temperature it shows antimagnetic characters. The spontaneous polarization and coercive field of PFN at room temperature are 11.5μC/cm2 and 3.04kV/cm, respectively. Dielectric measurement showed that the para-ferroelectric transition is diffusive character and the diffuse exponent is 1.62. Selected area electron diffraction pattern of PFN showed that the occupations of Fe3+ and Nb5+ ions in B site are disordered, leading to the diffuse characters of the para-ferroelectric transition.