John XIV, surnamed Kalekas (Greek: Ίωάννης ΙΔ' Καλέκας) (c. 1282–1347) was the Ecumenical Patriarch of Constantinople from 1334 to 1347. He was an anti-hesychast and opponent of Gregory Palamas. He was an active participant in the Byzantine civil war of 1341–1347 as a member of the regency for John V Palaiologos, against John VI Kantakouzenos.
John Kalekas was born about the year 1282 in Apros, Thrace. After having grown up in modest circumstances, John was married and had a son and daughter.
He was ordained a priest. John came under the patronage of John Kantakouzenos, the chief minister of emperor Andronikos III Palaiologos and later megas domestikos, who introduced him to the imperial court. In 1334, against the resistance of the Patriarchal Synod John Kantakouzenos led John Kalekas to his election, first, as Metropolitan of Thessalonica and, then, as patriarch of Constantinople, where he succeeded Isaias.
About the year 1337, during the patriarchate of John Kalekas, a Calabrian monk, Barlaam, who was the abbot of the Monastery of the St. Savior in Chora, learned of the practice of hesychasm during a visit to Mount Athos. Barlaam, trained in western scholastic theology, was scandalized and began to campaign against the practice and its advocate Gregory Palamas. The dispute grew until 1341, when emperor Andronikos III, a supporter of Gregory Palamas, convened the Fifth Council of Constantinople. Although he was supportive of Barlaam, John did not resist his condemnation; after his condemnation Barlaam left Constantinople permanently. Thereafter, Barlaam's cause was taken up by Gregory Akindynos. In 1344, in a synod convened by John Kantakouzenos, where the patriarch John was absent, Gregory Akindynos was also condemned.