Prince Kazimierz Czartoryski (4 March 1674 – 31 August 1741) was a PolishâÂÂLithuanian nobleman, Duke of Klewaà  and .
Kazimierz became Deputy cup-bearer of Lithuania in 1699, Grand Treasurer of Lithuania in 1707–1709, nominated by King Stanisà Âaw Leszczyà Âski. He was also Deputy Chancellor of Lithuania in 1712–1724. Castellan of Vilnius since 1724 and starost of Krzemieniec, Wielià ¼ and Uà Âwiaty.
He founded the "Familia" during the interregnum in 1696–1699. He supported the candidature of François Louis, Prince of Conti for the Polish throne in 1697.
In 1693 he married Izabela Morsztyn, daughter of Jan Andrzej Morsztyn and Katarzyna Gordon. They had three sons and two daughters.