Abstract. A data set consisting of twenty‐eight anatomical characters scored for twenty‐eight terminal taxa representing the world fauna of Signiphoridae was analysed using parsimony and compatibility methods. The Coccophaginae (Aphelinidae) and the Azotinae (Aphelinidae) were used as outgroups to establish polarity of character state changes. Relationships of Signiphoridae to other Chalcidoidea are discussed. Several multistate characters were treated in the parsimony analyses either as unordered or as ordered into transformation series using additive binary coding, which in some cases drastically reduced the number of equally parsimonious solutions. Monophyly of Signiphoridae is supported by seven synapomorphies. Four genera, Chartocerus, Thysanus, Clytina and Signiphora, are recognized within Signiphoridae based on synapomorphies. Rozanoviella syn.n. and Kerrichiella syn.n. are synonymized under Signiphora. Species of Signiphora are further assigned to four species groups, three of which are demonstrably monophyletic. Nine species or subspecies are transferred to Chartocerus from Signiphora (australicus comb.n., australiensis comb.n., australiensis orbiculatus comb.n., beethoveni comb.n., corvinus comb.n., funeralis comb.n., reticulata comb.n., ruskini comb.n., thusanoides comb.n.), one species to Thysanus from Signiphora (melancholicus comb.n.), and one species to Signiphora from Kerrichiella (coleoptratus comb.n.). A key to genera of Signiphoridae and species groups of Signiphora is presented. A diagnosis, relevant nomenclatural history, and a list of included species are given for each genus and species group, and the biology and distribution of each is summarized.