The EPR for two types of Fe3+-V-O defect in the PbTiO3: Fe3+ system has been investigated systematically by diagonalizing the complete energy matrix and considering the contributions from the spin-orbit coupling of the central ion as well as that of the ligand ions. Our results indicate that the doped ion Fe3+ will go away from oxygen vacancy (V-O) and the four planar oxygen ligands move towards V-O for B site in the PbTiO3: Fe3+ system and the obtained local lattice distortion parameters are well in accord with the experimental reports. Moreover, the links between the ground-state splitting and zeta, zeta' are discussed. (C) 2014 Elsevier B.V. All rights reserved.