Ludwig III (7 January 1845 - 18 October 1921) was briefly Prince Regent of Bavaria and was King of Bavaria from 1913 to 1918.

He was born in Munich, the son of Prince Luitpold of Bavaria (1821-1912) and his wife, Augusta of Tuscany (1825-1864)

On 20 February 1868, at Vienna, he married Maria Theresa, Archduchess of Austria-Este (1849-1919), daughter of Ferdinand of Modena (1821-1849) and his wife Elisabeth of Austria (1831-1903). On the death of her uncle Francis in 1875, she became heir to his Jacobite claim to the throne of England, and is called either Queen Mary IV and III or Queen Mary III by Jacobites.

Ludwig, on the death of his father, became regent for his insane cousin Otto of Bavaria in 1912, and deposed him by constitutional amendment and proclamation, with the subsequent assent of parliament, on 5 November 1913.

In 1918, on the eve of revolution, Ludwig and his family fled Munich, and on 13 November 1918 signed a paper that Kurt Eisner's government termed an abdication. On Eisner's death in 1919, Ludwig fled to Vaduz and from there to Hungary, where he died in Sárvár.

See also: List of rulers of Bavaria