| Otto Grieg Tidemand | |
| Office: | Minister of Defence |
| Primeminister: | Per Borten |
| Term Start: | 12 October 1965 |
| Term End: | 5 June 1970 |
| Predecessor: | Gudmund Harlem |
| Successor: | Gunnar Hellesen |
| Office2: | Minister of Trade and Shipping |
| Primeminister2: | Per Borten |
| Term Start2: | 5 June 1970 |
| Term End2: | 17 March 1971 |
| Successor2: | Per Kleppe |
| Birth Date: | 18 June 1921 |
| Birth Place: | Oslo, Norway |
| Death Place: | Oslo, Norway |
| Spouse: | Karin Lorentzen |
| Party: | Conservative |
Otto Grieg Tidemand (18 June 1921, Oslo – 10 June 2006, Oslo) was a Norwegian politician for the Conservative Party. He served as Minister of Defence from 1965 to 1970 and Minister of Trade and Shipping from 1970 to 1971.
During the Second World War, he served as a fighter pilot with the Royal Norwegian Air Force from 1942 to 1946, after training at a flying school in Canada. He was posted to No. 332 Squadron RAF (known as the Norwegian Squadron). While a sergeant pilot under training in England on 8 June 1943, he crashlanded his training plane near Ellesmere, Shropshire but survived unhurt. He flew Spitfires on offensive sweeps in Northwestern Europe and was credited with destroying one German Focke-Wulf Fw 190 and sharing in the downing of a Messerschmitt 410.[1]
From 1965 to 5 June 1970 he served as the Minister of Defence during the Per Borten cabinet. On that date, he was appointed Minister of Trade and Shipping, which he held until the Borten cabinet fell in 1971.[2]
He held numerous board memberships in Norwegian corporations, notably serving as chairman of the board of Saga Petroleum (1972-1976), Atlas Copco Norway (1978-1997), Vesta Hygea (1984-1986), Fina Norway (1981-1996) and Store Norske Spitsbergen Kulkompani (1982-1987).[2] He was a member of the Steering Committee of the Bilderberg Group[3] and participated in all their yearly conferences between 1967 and 1980 as well as in 1982 and 1984.
Tidemand was president of the Norwegian Golf Federation from 1962 to 1965.[2]