Disclosed is an ascorbic acid derivative or a salt thereof wherein at least one of hydrogen atoms in hydroxy groups at the 2-position and the 3-position of ascorbic acid is substituted by R-O-CH 2 -CH(OH)-CH 2 -, R-O-CH 2 -CH(CH 2 OH)-, R-CH(CH 2 OH)-, R-CH(OH)-CH 2 - (wherein R represents an alkyl group, an alkenyl group or a phenyl group), or a hydroxycyclohexyl group. Also disclosed is a method for producing an ascorbic acid derivative or a salt thereof, which is characterized by reacting ascorbic acid with an epoxy compound such as an alkyl glycidyl ether, an epoxy alkane or an alicyclic epoxy.
