Sergius I (died 966/967) was the second Duke of Amalfi [ citation needed ] and first of the Musco Comite family.
In 958, Sergius, a citizen of the city of Amalfi, assassinated the first duke, Mastalus II and usurped the throne.[ citation needed ] He ruled joinly with his son Manso I,[ citation needed ] in order to establish a ducal dynasty as in Naples and Gaeta. When he died, Manso's succession was smooth.
Sergius had other sons named John, Adhemar, and Leo, as well as a son named Adelfer, who later also usurped rule in Amalfi.[ citation needed ]