PURPOSE: To advantageously obtain an oxime corresponding to a raw material without previously synthesizing hydroxylamine and producing an inorganic salt as a by-product by directly reacting a ketone or aldehyde with nitrogen monoxide and hydrogen in the presence of a platinum group catalyst.

CONSTITUTION: A ketone or aldehyde is reacted with nitrogen monoxide and hydrogen in the presence of 0.001-20millimol, preferably 0.05-2millimol calculated as metal of a platinum group catalyst based on 1kg reaction solution at 10-150°C, preferably 30-80°C to give an oxime corresponding to the raw material such as cyclohexanone oxime. The oxime is economically advantageously obtained because a synthetic plant of hydroxylamine is not required and an inorganic salt such as ammonium sulfate is not produced as a by-product at all.