Australian Apiaceae, dominated by Hydrocotyloideae Link, are characterized by a number of enigmatic genera, the phylogenetic relationships of which are obscure. A cladistic analysis using morphological and anatomical data indicated that Apiaceae are monophyletic and Hydrocotyloideae form a grade between a paraphyletic Araliaceae and a monophyletic Apioideae Drude+Saniculoideae Burnett. Beyond this, there was no support for past suprageneric arrangements within the order. Hydrocotyleae Spreng. and their constituent subtribes were polyphyletic, as were the subtribes of Mulineae DC. The relationships between Australian genera were not well resolved although the analysis did provide a good indication of broad generic affinities.