Abstract: With high melting point,hardness,wear resistance,anti-corrosion,and other advantages,nano-sized chromic oxide (Cr<SUB>2</SUB>O<SUB>3</SUB>) is currently being developed and has a broad application prospect.Various preparation methods,including solid-phase methods (solid phase reaction method and mechano-chemical method),liquid-phase methods (micro-emulsion method,sol-gel method,supercritical fluid desolventizing method,radiation chemical synthesis method,hydrothermal me-thod,and deposition method),vapor-phase methods \[vapor condensation method,chemical vapor deposition method (CVD),physical vapor deposition method (PVD),and laser-induced pyrolysis method\],thermal spray method,and phase-transfer method of nano-sized chromic oxide were introduced.Advantages and disadvantages of those methods were briefly compared.Development trend and application prospect of nano-sized chromic oxide were described.