Nuri Demirağ (born 1886 in Divriği – died 1957 in Istanbul) was an early Turkish industrialist and railroad magnate. He was one of the first millionaires of the Turkish Republic.
His first enterprise was a cigarette paper factory which commenced production in 1922. Starting from the late 1920s, Demirağ began to invest his capital in the development of the Turkish railway network. Because of this investment, Mustafa Kemal Atatürk gave him the surname Demirağ (meaning "Iron web") when the Surname Law was put into effect in 1934.
In 1936 he established an aircraft factory employing 500 people in Beşiktaş, Istanbul (later nationalized by the government and now occupied by the Istanbul Naval Museum). The production of the Nu D.36 two-seat trainer biplane, and Nu D.38 twin-engine high-wing light transport plane took place in this factory.
In 1945 he founded the first opposition party, which was named Milli Kalkınma Partisi (National Development Party), but his party failed to receive the required amount of votes for entering the Turkish Parliament in the 1946 and 1950 general elections, and was eventually dissolved in 1958, a year after his death. In 1954, he was elected as a member of parliament for Sivas on behalf of the Democratic Party, which won the general elections.