Abstract： The electron paramagnetic resonance of Fe3+ ion in α-Al2O3 single crystal has been studies at room temperature in x-band. It is found that Fe3+ ions occupy actually four magnetically unequivalent sites. The Fe3+ ions in two kinds of sites between adjacent planes of oxygens have same Spin Hamiltonian Parameters (SHP), but have different SHP in the sites between next adjacent planes of oxygens. Two groups of SHP are: (1) g‖=2.001, g⊥= 2.003, D= 1679×10-4 cm-1, |a| =237×l0-4cm-1, a-F = 317×10-4cm-1. (2) g‖ = 2.001, g⊥= 2.006, D=l660×10-4cm-1, |a| = 243×10-4cm-1, a-F=338×10-4cm-1.