The Jones oxidation is an organic reaction for the oxidation of primary and secondary alcohols to carboxylic acids and ketones, respectively. It is named after its discoverer, Sir Ewart Jones.

Jones reagent is a solution of chromium trioxide in dilute sulfuric acid and acetone. A mixture of potassium dichromate and dilute sulfuric acid can also be used. The solvent acetone markedly affects the properties of the chromic acid. The oxidation is very rapid, quite exothermic, and the yields are typically high. The reagent rarely oxidizes unsaturated bonds.