Mellitus was the third Archbishop of Canterbury in the early 7th century AD.
Mellitus may also refer to: Diabetes mellitus, a metabolic disease Pachybrachis mellitus, a leaf-beetle species of Pachybrachis Neoporus mellitus, a predaceous water beetle in the family Dytiscidae Pyrophorus mellitus, a click beetle species of Pyrophorus Eumellitiphis mellitus, a bee mite in the family Laelapidae