To produce a hydroxy-substituted hydroxylamine derivative useful as an antioxidant to be included in a color photography developing composition by adding a specific epoxide to an aqueous solution of hydroxylamine, or the like, of free base form under specific condition.

The objective compound of formula III ((m), (n) and (p) are each 0 or 1) is produced by adding an epoxide of formula I or II (R' is H, an alkyl or the like; R1 and R2 are each H, an alkyl or the like; Y is an aliphatic group containing ≥4C or O atoms in the chain and having even number of atoms in the chain) to an aqueous solution of hydroxylamine or a monosubstituted hydroxylamine of free base form at an addition rate to keep the reaction temperature of the reaction solution to ≥50°C while keeping the molar ratio of the total amount of the added epoxide to the solution to 2: (1-1.2).