Count Adolf III of Nassau-Wiesbaden-Idstein (by a different way of counting: Adolf IV; 10 November 1443 – 6 July 1511) was a son of Count John II of Nassau-Wiesbaden-Idstein and his wife Mary of Nassau-Siegen (1418–1472).

After his father's death in 1480, he ruled Nassau-Wiesbaden and his brother Philip ruled Nassau-Idstein.

Adolf served in the army of the Habsburg Duke consort and later Emperor Maximilian I and participated in the conquest of the Duchy of Gelre in 1478.

However, in 1492 Charles II was reinstated as Duke of Guelders.

Adolf then returned to Germany[1] He married in 1484 to Margarethe von Hanau-Lichtenberg, a daughter of Philip I of Hanau-Lichtenberg.