Adalbert was the third Margrave of Austria. He ruled for nearly four decades in the 11th Century.

Like many people in early medieval times, Adalbert had few details of his early life recorded. His father was the first Magrave of Austria, Leopold the Illlustrious, and his mother was Richardis of Sualafeldgau. Adalbert was their third son, born about 985.

His oldest brother was Henry, who succeeded their throne as margrave in 994. The Holy Roman Emperor Henry II had granted Henry additional lands in 1002, and the margraviate's new neighbors proved problematic to Austrian peace. Henry won two significant victories against his Polish neighbor. In 1015, Ernest, younger brother of Henry and older brother of Adalbert, died. Thus, Adalbert was next in line to rule.

When Henry died three years later, Adalbert succeeded him. He made his headquarters the castle of Melk, which his father had taken from his enemy Burkhard. Adalbert followed in his father's and brother's footsteps by extending the borders of the realm. He also lent support to the Holy Roman Emperor Henry III, who was engaged in struggles against both Bohemia and Hungary.

Adalbert married twice, first to Gilsmod of West Saxony and then to Frozza Orseolo. From the second marriage came one child, Ernest, who succeeded his father when Adalbert died in Melk on May 26, 1055.