He was the son of Burchard II and Regilinda. At a young age on the murder of his father in 926, he was sent to Saxony for his safety after the accession of the duke Herman I. In Saxony, he married a member of the Immedinger family. From this marriage came two sons: Theodoric, count of Wettin, and Burchard, count of Liesgau. He second marriage was to Hedwige, daughter of Henry I, Duke of Bavaria. Burchard built the great fortress atop the Hohentwiel, and Hedwige was the foundress of the monastery of St. Georg there, but their marriage remained childless.
After the rebellion of Duke Liudolf, son of King Otto I, in 954, the king bestowed the ducal title on his nephew-in-law Burchard at a general council at Arnstadt. Burchard was an intimate of Otto and his queen, Adelaide of Italy. He was often at the royal court and he accompanied Otto on his campaign against the Magyars and was present at the great Battle of the Lechfeld on August 10 955. In 965, he led a third campaign against Berengar II in Italy. At the Battle of the Po on 25 June, Burchard defeated the local Lombard magnates and restored Italy to Ottonian control, even the south Italian principalities were brought to heel by 972. In 973, he died and was buried in the chapel of Saint Erasmus in the monastery on Reichenau Island in Lake Constance. He was succeeded by Otto, son of Liudolf.