|Named By:||George Gaylord Simpson in 1927|
|Time Period:||Late Cretaceous|
|Size:||Estimated about 30 centimetres long|
|Classification:||| Chordata | Mammalia | Marsupialia | Ameridelphia | Didelphimorphia ||
Alphadon (meaning "first tooth") was a genus of small, primitive mammal that was a member of the metatherians, a group of mammals that includes modern-day marsupials. Its fossils were first discovered and named by George Gaylord Simpson in 1929.