Johan Martin Ferner (né Johan Martin Jacobsen; 22 July 1927 – 24 January 2015) was a Norwegian sailor and Olympic medalist. He won a silver medal in sailing at the 1952 Summer Olympics in Helsinki. He was married to Princess Astrid of Norway.
Johan Martin Jacobsen was born on 22 July 1927 in Oslo, the son of master tailor Ferner Jacobsen (1884–1964) and his wife, Ragnhild Olsen (1889–1966). His grandfather was maritime pilot Johan Martin Jacobsen (1850–1907) from Tjøme, son of blacksmith Jacob Andreas Knudsen (1819–1868). His family adopted their father's given name, Ferner, as their family name.
He studied business in Norway, at the London Polytechnic Institution and Bradford Technical College in England and at the University of Lyon in France. At his father's death in 1964, he and his brother, Finn Ferner, took over the management of the family clothing company, Ferner Jacobsen.
At the 1952 Summer Olympics in Helsinki, Ferner won the silver medal in sailing in the 6 metre class with the boat Elisabeth X, together with his brother Finn Ferner, Erik Heiberg, Tor Arneberg and Carl Mortensen.
Firstly, on 20 January 1953, Johan Ferner married artist Ingeborg 'Bitte' Hesselberg-Meyer (later Rostad; 1931–1997). They divorced in 1956. He then remarried at Asker Church on 12 January 1961 to Princess Astrid of Norway (1932–2026), the second daughter of King Olav V of Norway and Princess Märtha of Sweden.
Ferner died on 24 January 2015 at the National Hospital in Oslo, at the age of 87.
Cathrine Ferner (b. 22 July 1962)
Benedikte Ferner (b. 27 September 1963)
Alexander Ferner (b. 15 March 1965)
Elisabeth Ferner (b. 30 March 1969)
Carl-Christian Ferner (b. 22 October 1972)
Norway: Knight Commander of the Order of St. Olav
Norway: Recipient of the Medal of the 100th Anniversary of the Birth of King Haakon VII
Norway: Recipient of the King Olav V Silver Jubilee Medal
Norway: Recipient of the King Olav V Commemorative Medal
Norway: Recipient of the Medal of the 100th Anniversary of the Birth of King Olav V
Norway: Recipient of the Royal House Centenary Medal
Belgium: Knight Grand Officer of the Order of Leopold II