The Diocese of Termoli-Larino is a Latin Church diocese of the Catholic Church situated in the province of Campobasso, region of Molise. The commune of Termoli is an important regional seaport. The diocese has existed in its current configuration since 1986, when the diocese of Larino was suppressed and added to its territory. It is a suffragan of the archdiocese of Campobasso-Boiano.