Karl Marthinussen (1890–1965) was a Norwegian theologian and priest.
[1] Bishop Marthinussen was born on 26 November 1890 in Bergen, Norway.
He was hired as a priest at the St. Jakob parish in Bergen from 1916 until 1930.
In 1934, he was named the chairman for the Christian Democratic Party in Bergen.
He worked at the Sandvik Church until 1948 when he was appointed the Bishop of the Diocese of Stavanger.