Siminina, was a Roman era civitas of the Roman province of Africa Proconsularis.
The ancient city is tentatively identified with ruins at Bir-El-Djedidi, Tunisia.
The city was also the seat of an ancient Christian bishopric, suffragan of Archdiocese of Carthage.
Only two bishops of Siminina are documented Today Siminina survives as a titular bishopric.
From 17 December 2024 the titular bishop is Iyad Twal, auxiliary bishop of the Latin Patriarchate of Jerusalem.