He was born as the first child and only son of Frederick William II, Duke of Schleswig-Holstein-Sonderburg-Beck and his second wife, Burgravine Ursula Anna of Dohna-Schlodien (1700-1761).

Frederick William was a recipient of the Order of the Red Eagle.

He served as a colonel in the Prussian Army and was commander of the Füsilier Regiments No.

During the Seven Years' War, he fell in the Battle of Prague in 1757.

He was unmarried and childless; he was succeed as Duke of Schleswig-Holstein-Sonderburg-Beck by his uncle Charles Louis.