Friedrich, Duke of Schleswig-Holstein-Sonderburg-Glücksburg, since 1931 of Schleswig-Holstein (23 August 1891 – 10 February 1965) was the Duke of Schleswig-Holstein and Head of the House of Oldenburg from 21 January 1934 until his death on 10 February 1965.

Prince Friedrich was born on 23 August 1891 at Grünholz Manor in Schleswig-Holstein, Prussia as the fifth child and only son of Frederick Ferdinand, Duke of Schleswig-Holstein-Sonderbug-Glücksburg and his wife Princess Karoline Mathilde of Schleswig-Holstein-Sonderburg-Augustenburg.

Prince Friedrich's father was the eldest son of Friedrich, Duke of Schleswig-Holstein-Sonderburg-Glücksburg and a nephew of Christian IX of Denmark. Upon the death of his father in 1885, he had succeeded to the headship of the House of Schleswig-Holstein-Sonderburg-Glücksburg and the title of duke.

Friedrich married his second cousin, Princess Marie Melita of Hohenlohe-Langenburg, daughter of Ernst II, Prince of Hohenlohe-Langenburg and his wife Princess Alexandra of Saxe-Coburg and Gotha, on 5 February 1916 at Coburg. Friedrich and Marie Melita had four children.

When the Head of the House of Schleswig-Holstein-Sonderburg-Augustenburg Albert, Duke of Schleswig-Holstein died on 27 April 1931, Friedrich's father Friedrich Ferdinand became the Head of the House of Oldenburg and inherited the title of Duke of Schleswig-Holstein.

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