Demetrio may refer to: Demetrio, a variant of the name Demetrius Demetrio (Metastasio), an opera libretto in three acts by Pietro Metastasio Demetrio (1773), set by Josef Mysliveček Demetrio (1779), reset by Josef Mysliveček Demetrio (Mayr), set by Simon Mayr See also Demetrius (disambiguation) San Demetrio (disambiguation)