The invention relates to a process for purifying a crude 1,1,1,5,5,5-hexafluoroacetylacetone dihydrate containing an impurity. The process includes bringing the crude 1,1,1,5,5,5-hexafluoroacetylacetone dihydrate into contact with a poor solvent in which 1,1,1,5,5,5-hexafluoroacetylacetone dihydrate is substantially insoluble, thereby removing the impurity from the crude 1,1,1,5,5,5-hexafluoroacetylacetone dihydrate. Alternatively, the process includes precipitating crystals of 1,1,1,5,5,5-hexafluoroacetylacetone dihydrate from a solution of the crude 1,1,1,5,5,5-hexafluoroacetylacetone dihydrate. Thus, it is possible to produce 1,1,1,5,5,5- hexafluoroacetylacetone dihydrate of high purity. This product makes it easy to produce 1,1,1,5,5,5-hexafluoroacetylacetone of high purity.