The current mayor is Piero Castrataro, supported by the centre-left coalition, who took office on 19 October 2021.

[1] According to the Italian Constitution, the mayor of Isernia is member of the city council.

The mayor is elected by the population of Isernia, who also elect the members of the city council, controlling the mayor's policy guidelines and is able to enforce his resignation by a motion of no confidence.

The mayor is entitled to appoint and release the members of his government.

Since 1998, under provisions of new local administration law, the Mayor of Isernia is chosen by direct election.