A process for producing cyclohexanone oxime is provided: (1) reacting cyclohexanone, hydrogen peroxide and ammonia in the presence of a titanosilicate catalyst to give a reaction solution containing cyclohexanone oxime, water, unreacted ammonia and unreacted cyclohexanone, (2) distilling off ammonia, (3) an extraction step, (4) mixing the organic layer obtained in step (3) with water followed by separating into an organic and aqueous layers, (5) distilling off organic solvent and water to obtain a bottom product containing cyclohexanone oxime and cyclohexanone, and (6) distilling off cyclohexanone and to obtain a bottom product containing cyclohexanone oxime; wherein a compound selected from an oxide, an oxo acid, an oxo acid salt, an oxo acid ester and an oxo acid amide of boron or phosphorous is added to at least one of the water used in the step (4) and the organic layer obtained in step (4) to be subjected to step (5).