Hydantoin derivatives and salts thereof, intermediates therefor, process for the preparation thereof, and medicines containing the derivative, wherein said derivatives have the formula ##STR1## wherein one of V and W is hydrogen and the other is a halogenomethyl group, 1H-tetrazol-5-yl radical, --COOR group,in which R is hydrogen atom, an alkyl group, --(CH.sub.2 CH.sub.2 O)nCH.sub.3 group (n is an integer of 1 to 113) or substituted phenyl, ##STR2## in which R.sub.1 and R.sub.2 are same or different independently, each is hydrogen atom, an alkyl group, substituted phenyl or --(CH.sub.2 CH.sub.2 O)nCH.sub.3 group (n has the meaning as referred to) or R.sub.1 may form a heterocyclic ring together with R.sub.2 and nitogen or oxygen atom,--CH.sub.2 OH.sub.3 group or ##STR3## group, in which R.sub.3 and R.sub.4 are same or different independently and each is hydrogen atom or an alkyl group,X is oxygen or sulfur atom, and Y and Z are same or different independently and each is hydrogen atom, a halogen atom, alkyl group, alkoxy group, alkylmercapto group, nitro radical or --NHR.sub.5 group, in which R.sub.5 is hydrogen atom or an acyl group.The derivatives and salts thereof are useful for the treatment of complications of diabetes.