The Naab (; ) is a river in Bavaria, Germany.
This 97.5 kilometer long river is a left tributary of the Danube. Its average discharge at the mouth is .
The Naab is formed by the confluence of the Waldnaab and the Haidenaab in Luhe-Wildenau, south of Weiden in der Oberpfalz. It flows generally south, through the towns Nabburg, Schwandorf and Burglengenfeld. It flows into the Danube near Regensburg.