Burg Wiener Neustadt is a castle in Wiener Neustadt, Lower Austria, Austria. The first castle in Wiener Neustadt was built in 1193/94, when at the same time, the city walls of Wiener Neustadt were built. The costs were paid from the ransom of Richard the Lionheart. This castle is said to have stood on the north-eastern corner of the city, but there is no archaeological evidence of this.
When that castle became too small, however, the newer castle was built on the present site by Leopold VI the Glorious at the beginning of the 13th century. Since the area is quite marshy, it was built on wooden piles. Under Frederick II the Warlike it was finally surrounded by a moat, outer walls and towers.