Majolus of Cluny (Maieul, Mayeul, Mayeule, Mayol) (c. 906 – May 11, 994) was the fourth abbot of Cluny. Majolus was very active in reforming individual communities of monks and canons; first, as a personal commission, requested and authorized by the Emperor or other nobility. Later, he found it more effective to affiliate some of the foundations to the motherhouse at Cluny to lessen the likelihood of later relapse.

He travelled widely and was recognized as a person of influence both at Rome and the Imperial court. He is buried at the Priory of Souvigny, along with Odilo, the fifth abbot of Cluny, and commemorated individually on May 11, and also on April 29 with four other early abbots of Cluny.

There are two "lives" written about Majolus: one by Syrius, a monk of Cluny; and one by Odilo, the fifth abbot of Cluny.

Majolus' father, named "Fulcher", was from a wealthy provincial family of Avignon. His mother was named Raimodis. They had two sons: Majolus and Cynricus. It is not known for sure which was the older, but traditionally the younger sons of noble families were given to the church and the elder sons were made the heirs to the father's estate, hence because Majolus became a monk, it is sometimes assumed he is the younger.

Around 916, Majolus fled his family's estates near Rietz to stay with relatives at Mâcon due to the feudal wars. Both his parents died while he was young.

Majolus studied the liberal arts at Lyon and became canon, and later archdeacon of Mâcon; his ordination to the priesthood was in Mâcon. While in Mâcon he gave classes to a large body of clerks for free. He built a small oratory on the opposite side of the river from the town, where he would retire for prayer. In personal habits he was always kind, never telling lies, detraction or flattery, and he was severe against sinners, if it was necessary to call them to repent. He gained a reputation among the local people as a holy person and so when Besançon needed a new bishop, many people, called on him to become bishop, but he refused.

There was a famine at the time and Majolus prayed for help for those begging for food. One day as he prayed seven solidi (gold coins) appeared in front of him. He was afraid that this was a trick from the devil or that the money was lost, and he wouldn't touch it. But when he discovered the money was real and no one claimed it, he then used it to buy food for the poor that were starving.

He decided instead to enter Cluny Abbey, which he had visited previously. Aymard of Cluny was Abbot at the time. Aymard appointed Majolus "armarius" (book-keeper and master of ceremonies). He was later made librarian. He had read the poems of Virgil and he considered that monks should not read these works, but that the Bible alone was enough for them. He was very harsh in the discipline he applied to new monks.