Theognostus (Russian: Феогност, Feognost; died 11 March 1353) was a bishop of the Ecumenical Patriarch of Constantinople who served as Metropolitan of Kiev and all Rus'.

Theognostus was born in Constantinople and later in his life became Peter's successor as Metropolitan of Kiev and all Rus'.

[1] It was his lot to reconcile Novgorod with the Grand Duchy of Moscow in times of their mutual animosity.

It was the Khan who finally gave up and confirmed the existing privileges of the Russian Orthodox Church.

In 1353, feeling that his days were numbered, Theognostus recommended Alexius (Bishop of Vladimir) his successor.