Maximilian III Joseph, Elector of Bavaria (28 March 1727-30 December 1777) was the eldest son of Emperor Karl VII. Upon his father's death in 1745, he inherited a country in the process of being invaded by Austrian armies (see War of the Austrian Succession), and quickly abandoned his father's imperial pretenses and made peace with Maria Theresa in the Treaty of Füssen, in which he agreed to support her husband, Grand Duke Francis Stephen of Tuscany, in the upcoming imperial election.

The remainder of his reign was uneventful. As the last of the junior branch of the Wittelsbach dynasty which ruled Bavaria, his death led to a succession dispute and the brief War of the Bavarian Succession. Ultimately, he was succeeded by his distant cousin, the Elector Palatine Karl IV.