Gerhard (or Gerard) of the Moselle (Latin Gerhardus Mosellensis), Count of Metz and possibly of Alsace (approximately 970-1025[1]), was a Lotharingian noble active in the early 11th century. He was a key figure within an alliance of Lotharingian nobles who were seen as opponents of Henry II, Holy Roman Emperor. This also put him in constant conflict with the king's loyal representatives in Lotharingia, his relatives in the family known to historians as the House of Ardenne–Verdun. Henry II was Gerhard's brother-in-law, as they had both married daughters of Count Sigfried, the ancestor of the counts of Luxembourg. Sigfried was also in the Ardenne dynasty, though his family came to be opposed to his Verdun cousins.
Gerhard was thus a part of the rebellion of his in-laws the Luxembourg family, led by Sigfried's eldest son Henry V, Duke of Bavaria. Gerhard was also an ally of the family who had been Henry II's competitors for the throne, and who took over the crown after him, the so-called Salian dynasty. His sister's son became Conrad II, Holy Roman Emperor.