<p>A composition which contains a polyglycerol/medium-chain fatty acid ester and can form a water-in-oil type microemulsion capable of containing a large quantity of solubilized water and which is excellent also in dispersibility and self-emulsifiability in water; and a cosmetic preparation containing the composition. The composition comprises: a polyglycerol/medium-chain fatty acid ester obtained by the esterification of a C6-10 fatty acid and a polyglycol having an average degree of polymerization of 3 to 100, excluding 100; and a nonionic surfactant.</p>
