Sadık Necmettin Sadak (1890 in Isparta, Ottoman Empire – 21 September 1953 in New York City) was a Turkish politician, former minister of Foreign Affairs of Turkey and former chairman of the Turkish sports club Galatasaray.

After graduating from Galatasaray High School in 1910, he studied humanities in the University of Lyon, France, until 1914.

After his return to Turkey, he started to work in fields of sociology.

In 1928 he was elected as member of national parliament from Sivas province .

His political success continued and he was elected again for five consecutive times to parliament.