Chorological and phenological analyses of the aquatic beetle fauna (Gyrinidae, Haliplidae, Hygrobiidae, Noteridae, Dytiscidae, Hydrophilidae, Hydraenidae, Dryopidae, Elmidae, and Scirtidae) of northern Tunisia are presented. Water beetles were sampled from freshwater ecosystems at 64 sites distributed throughout northern Tunisia. In total, 123 species were identified and their distribution in the study area is discussed. Chorological categories were determined according to the geographical distribution of sampled species. Three groups of species were established based on their phenology: permanent, frequent, and seasonal species.