Allodiscus is a genus of land snails belonging to the family Charopidae. The genus was described by Henry Augustus Pilsbry in 1892.
Pilsbry in 1892 originally described Allodiscus as a subgenus of Helix, naming H. dimorpha (Allodiscus dimorphus) as the type species. A revision of the genus in 2008 saw the addition of 31 new species.
The genus is found in New Zealand, the New Zealand Subantarctic Islands and on New Caledonia.