Saint Genesius of Lyon (Genestus, Genes) (died 679) was the 37th Archbishop of Lyon.
He was a native of France, not of Arabia or Armenia as is sometimes stated and became a religious and abbot (though not of Fontenelle Abbey), attached to the court and camp of Clovis II. There he acted as chief almoner to the queen, Bathildis.
He succeeded St. Chamond (Annemundus) in the See of Lyon, and was consecrated in 657 or 658. His name is found for the first time as bishop in a signature of 6 September, 664, attached to a charter drawn up by Bertefred, bishop of Amiens, for the Abbey of Corbie.
On 26 June, 667, he subscribed another charter framed by Drauscius, Bishop of Soissons, for a convent of the Blessed Virgin founded by Ebroin, mayor of the palace, and his wife Leutrude. In the conflict between Ebroin and St. Leger (Leodegarius), Bishop of Autun, Genesius (675-76) took the part of the bishop and was in consequence attacked by an armed band sent by Ebroin to expel him from Lyons; but Genesius collected a force and successfully defended his city.
In September, 677, he assisted at an assembly held at Maslay-le-Roi or more probably Marly-le-Roi. He was succeeded at Lyon by Landebertus otherwise Lambertus. His body remained in the church of St. Nicetius (St-Nizier) till the beginning of the fourteenth century, when it was transferred to Chelles.
He is a Catholic saint, feast day 1 November.