Louis Christian Oliver Zachariasen known as Louis Zachariasen (21 January 1890 in Kirkja, Fugloy – 30 August 1960) was a Faroese writer and politician for the New Self-Government party. He was the first deputy prime minister of the Faroe Islands after the islands received home rule in 1948.
Zachariasen received a degree as a schoolteacher from the Faroese Teachers School in Tórshavn in 1911 and attended a folk high school in Denmark in 1915. In 1918 he received his examen artium, and in 1924 he received a master of science in engineering (Danish: cand.polyt.) from Polyteknisk Læreanstalt in Copenhagen. He moved back to the Faroe Islands, where he was employed by the Faroese Telephone Company (Telefonverk Føroya Løgtings) in 1925, and he served as the CEO of the company from 1936 to 1952. He was also the president of the Collegium Academicum Faeroense from 1933 to 1942.