Alexander may refer to any of the following:
- Alexander, the Martyr (February 25)
- Alexander, the Martyr (February 27)
- Alexander, the Martyr (March 9)
- Alexander, the Martyr (March 14)
- Alexander, Pope of Rome (March 16)
- Alexander, the Martyr from Pidni (March 14) Gr. ο εν Πίδνη
- Alexander, the Martyr (April 1)
- Alexander, the Martyr (A) (April 10)
- Alexander, the Martyr (B) (April 10)
- Alexander, Priest-Martyr (May 13)
- Alexander, the Martyr (A) (May 14)
- Alexander, the Martyr (B) (May 14)
- Alexander, Archbishop of Jerusalem (May 16)
- Alexander, the Martyr (May 20)
- Alexander of Thessaloniki the New-Martyr (May 26)
- Alexander, Bishop of Thessaloniki (May 28 and final Sunday after Easter)
- Alexander, Archbishop of Alexandreia (May 29)
- Alexander, Priest-Martyr and Bishop of Prousa (June 9)
- Alexander, the Martyr (June 10)
- Alexander the Doctor, Martyr (July 25), see also St. Saktos (Gr. Σάκτος)
- Alexander, the Martyr (August 1)
- Alexander of Ikonio (August 21), Gr. εν Ίκονίω
- Alexander Nevsky, the Grand Prince of Novgorod and Vladimir (August 30, November 23)
- Alexander, Patriarch of Constantinople (August 30)
- Alexander, the Martyr (A) (September 28)
- Alexander, the Martyr (B) (September 28)
- Alexander the Bishop, Priest-Martyr (October 22)
- Alexander, the Martyr (October 30)
- Alexander, the Martyr from Thessaloniki (November 7)
- Alexander, Bishop of Mithimna (November 30)
- Alexander, the Martyr (November 24)
- Alexander, Priest-Martyr and Archbishop of Jerusalem (December 12)
- Alexander, Virgin-Martyr (December 17 and July 9)
- Alexander (December 29), see also the Bio of St. Markellos.