Prince August Aleksander Czartoryski, 9 November 1697 – 4 April 1782) was a Polish noble (szlachcic), magnate, and founder of the family fortune.
August became major-general of the Polish Army in 1729, voivode of the Ruthenian Voivodeship in 1731, general starost of Podolia in 1750–1758, and a Knight of Malta.
He was starost of Warsaw, Koscierzyna, Lubochnia, Kalusz, Latowicz, Lucyn, Wawolnica, Kupiski and Pienian.
He supported Stanislaw Leszczynski during the War of the Polish Succession in 1733.
In the reign of August III, with his brother Michal he was a leader of the "Familia." During the interregnum of 1763–64 he strove for the Polish crown for himself, later for his son Adam Kazimierz.
In 1764–66 he was marshal of the General Confederation (konfederacja generalna); from 1764, Regimentarz of the Crown.
He was a supporter of political reforms in the Republic, and an opponent of the Radom Confederation.