This paper reports the gill morphology of seven common gastropods from Moreton Bay, southeastern Queensland, to test the level of difference in gill structure between major taxa. The investigated species include representatives of the clades Patellogastropoda, Neritimorpha and Vetigastropda as well as representatives of the more ‘advanced’ Caenogastropoda. Examination by SEM and LM revealed that the external gill structure of the investigated caenogastropods (including Planaxis sulcatus, Littoraria articulata, Bembicium auratum and Morula marginalba) shows basic uniformity. The gill filaments are composed of a clearly defined ridge and an extended sheet of non-ciliated cells. The gill filaments of these species differ in the shape of the filaments (corrugated, triangular or rounded) and the presence of secretory cells. The gills of the limpet Patelloida mimula and neritid Nerita chameleon, representatives of the clades Patellogastropoda and Neritimorpha respectively, are both triangularly shaped, but differ by the presence of paddle shaped cilia in the former species and secretory cells in the latter. The gill morphology of the vetigastropod trochid Austrocochlea constricta, characterized by blade shaped filaments covered with nodules and a striped pattern of ciliated cells, showed the least similarities with the other investigated species.