The Roman Catholic Diocese of Pathein (Lat: Diocesis Patheinensis) is a diocese of the Latin Rite of the Roman Catholic Church in Burma.
The diocese was erected as the diocese of Bassein in 1955, from the vicariate apostolic of Rangoon, which eventually became the Archdiocese of Yangon.
In 1991, the name of the diocese was changed to the diocese of Pathein. The diocese is a suffragan of the Archdiocese of Yangon.
The current bishop of the diocese is John Hsane Hgyi, appointed in 2003.