Pollen morphological investigations of the family Haloragaceae were carried out using light microscopy supplemented by electron microscopical studies. An attempt was made to correlate the pollen morphology with the taxonomy of the family. The pollen morphological data provide clear support in favour of the division of the family into two separate families, respectively, Haloragaceae and Gunneraceae. Both subfamilies, i.e., Haloragoideae Schindl. (excluding a few species in the subsection Spongiocarpus Schindl.) and Gunneroideae Schindl., are stenopalynous. Important arguments concerning pollen morphology, gross morphology, ecology, and type of pollination, favour a regroupment of theHaloragisspecies belonging to the subsection Spongiocarpus, which is related to the genusLaudoniaLindl. Eventual fusion of theseHaloragisspecies in the subsection Spongiocarpus with the genusLoudoniais worth consideration.