Chromium oxide may refer to:
Chromium(II) oxide, CrO Chromium(III) oxide, Cr2O3 Chromium dioxide (chromium(IV) oxide), CrO2, which includes the hypothetical compound chromium(II) chromate Chromium trioxide (chromium(VI) oxide), CrO3 Chromium(VI) oxide peroxide, CrO5 Mixed valence species, such as Cr8O21
See also Chromate and dichromate CRO (disambiguation)