The present invention relates to a dermatologic preparation containing a
diamide derivative represented by the following formula (1): ##STR00001##
(wherein, R.sup.1 represents a linear or branched hydrocarbon group
having 1 to 22 carbon atoms which may be substituted by one or more
hydroxy and/or alkoxy groups, R.sup.2 represents a linear or branched
divalent hydrocarbon group having 1 to 12 carbon atoms, and R.sup.3
represents a linear or branched divalent hydrocarbon group having 1 to 42
carbon atoms). This diamide derivative (1) is capable of fundamentally
improving the water retention capacity and barrier functions of the horny
layer, is excellent in miscibility and mixing stability and can be
prepared efficiently at a low cost.