Oluf Christian Dietrichson (3 May 1856 – 20 February 1942) was a Norwegian explorer and military officer. He was a member of the Greenland expedition of 1888 led by Fridtjof Nansen, the first documented crossing of Greenland.
Oluf Dietrichson was born at Skogn (now Levanger) in Nord-Trøndelag, Norway. His father, Peter Wilhelm Kreidahl Dietrichson, was employed as the senior doctor at the Nord-Trøndelag Hospital. He received a military education and was commanding officer in Kristiansand from 1918 to 1924. Dietrichson continued his military career and advanced to Major General.
In 1888, Fridtjof Nansen assembling a team for the purpose of crossing the Greenlandic ice-sheet. Dietrichson participated as a metrological surveyor, surveyor and map marker. The other participants at the Greenland expedition were Otto Sverdrup, Samuel Balto, Ole Nielsen Ravna and Kristian Kristiansen.