The Diocese of Lucknow is a diocese of the Church of India CIPBC, headquartered in the city of Prayagraj.

The jurisdiction of the diocese mainly covers the Eastern side of Uttar Pradesh.

The diocese was given the name of Lucknow although the mother Cathedral, All Saints Cathedral and diocesan headquarters stayed in Prayagraj.

It was because Prayagraj was situated within the legally defined territories of the diocese of Calcutta.

The Bishop of Lucknow was the Ordinary of the Anglican Diocese of Lucknow from its inception in 1893 until the foundation of the Church in India, Pakistan, Burma and Ceylon in 1927 and its consequent merger with other Protestant Churches to form the Church of India in 1927; and since then head of one of the united church's biggest dioceses.