The Cr2O3 thin films were grown on Al2O3(1102)(r-cut sapphire), Al2O3(1120)(a-cut sapphire), and Al2O3(0001)(c-cut sapphire) substrates to apply magnetoelectric oxides to oxides electronics. The Cr2O3 is a representative magnetoelectric material with antiferromagnetic insulator with the Néel temperature of 308 K. From the results of X-ray diffraction and the reflection high energy electron diffraction, epitaxial Cr2O3 thin films were obtained on all cut sapphire substrates using off-axis DC-RF magnetron sputtering method. The epitaxial relationship was Cr2O3//Al2O3 and Cr2O3(1102)//Al2O3(1102) on r-cut, and Cr2O3//Al2O3 and Cr2O3(1120)//Al2O3(1120) on a-cut, and Cr2O3//Al2O3 and Cr2O3(0001)//Al2O3(0001) on c-cut. Optimized Cr2O3 film was obtained grown at 600°C on c-cut sapphire substrate. The surface roughness (Ra) of the film was 0.28 nm, and full width at half maximum of rocking curve for Cr2O3(0006) Bragg reflection was 0.23°. Growth difference is expected to be caused by the stacking order of atoms normal to the substrate surface and arrangement of atoms of the substrate surface.