John Olav Krog

John Olav Krog (29 August 1918 – 26 April 2007) was a Norwegian zoophysiologist.

He was born in Meldal as a son of a teacher. He finished his secondary education at Orkdal Landsgymnas in 1938. He underwent initial officer's training in 1940, later fled to Sweden where he joined the Norwegian police troops, later the Independent Norwegian Brigade Group in Germany,

Krog was a research fellow at Ullevål Hospital from 1954, and prosector from 1962. In 1964 he took the dr.philos. degree with the doctoral thesis A comparative study on the effect of cervical sympathetic stimulation on cerebral blood flow. Following that he was appointed as a professor of zoophysiology at the University of Oslo in 1966.

Krog retired in 1988. Main hobbies included hunting and fishing. He died in April 2007, aged 88.