Adalbert (German: Albrecht), known as Adalbert the Victorious (German: Albrecht der Siegreiche), was the Margrave of Austria from 1018 until his death in 1055. He was a member of the House of Babenberg.
Adalbert was the third son of Leopold the Illustrious and Richardis of Sualafeldgau. He succeeded as Margrave upon the death of his older brother, Henry I, Margrave of Austria.
As Margrave, he extended the eastern border of the then small Ostmark of Bavaria as far as the rivers Morava/March and Leitha and supported King Henry III in his battles against Hungary and Bohemia. He resided in the Lower Austrian Babenberg castle of Melk, where Melk Abbey was to develop later.
Adalbert died on 26 May 1055 at Melk.