The Diocese of Fissiana (Latin: Fissianensis) is suppressed Latin Church diocese and current titular see of the Catholic Church.

The exact location for the seat of the diocese is unknown,^[1] though Fissiana, is tentatively located somewhere near Foussana in modern Tunisia. In antiquity it was within the Roman province of Byzacena,^[2][3] corresponding to the modern Sahel region of Tunisia.

Of this dioceses only two Donatist bishops are known.

• Donato who participated in the Council of Cabarsussi, held in 393 by Maximianus, a dissident sect of the Donatists, and he signed the acts of that Council.
• At the Council of Carthage (411), Bishop Turrasio represented the town, no Catholic competitor attended the conference.

That the town was a stronghold of Donatism is not surprising, as it is located close to the heartland of that movement with many of the first Donatist congregations forming in the semi-arid region to the west and south west of Foussana.

Today Fissiana survives as titular bishopric^[1] and the current bishop is Darius Trijonis, Auxiliary bishop of Vilnius.^[4]

• Donato (fl 393) (Donatist)
• Turrasio (fl 411) (Donatist)
• Francis Arinze (Nigeria) 6 July 1965 – 26 June 1967
• Leo Rajendram Antony (Sri Lanka) 3 August 1968 – 15 February 1974
• Joseph Valerius Sequeira (Myanmar) 20 October 1984 – 24 January 1986
• Julio Ojeda Pascual (Peru) 30 March 1987 – 28 April 2013
• Fernando Martín Croxatto (Argentina) from 13 March 2014 – 3 August 2017
• Darius Trijonis (Lithuania) 29 September 2018 – present