Marta Steinsvik (23 March 1877 – 27 July 1950) was a Norwegian author and translator. She was a champion of women's rights, a proponent of anti-semitism and anti-Catholicism, and promoter of the use of Nynorsk. She was the first female to graduate from the Norwegian School of Theology.
Steinsvik was born in Flekkefjord. he studied medicine in Kristiania, but never finished her studies because she was against vivisection. She studied several other subjects including Egyptology in London. In 1902, Marta Steinsvik studied oriental languages including Assyrian and ancient Egyptian. She also became interested in Esotericism. She was influenced by the thinking of both English Theosophist, Annie Besant and Austrian philosopher, Rudolf Steiner. She was the first woman to graduate from the Norwegian School of Theology, but was not allowed to practice. She was the first Norwegian woman to preach in a church, during 1910 at the Grønland church in Oslo. She was invited to an international women's conference in Geneva, and planned to give a talk on women priests, until the Pope forbade all Catholic women to attend if she did, forcing her to give a speech on another subject.
In 1894 she started writing in the newspaper, Den 17de Mai, which had been started that same year by her future husband Rasmus Steinsvik. She was employed as secretary to Hans Tambs Lyche, editor and founder of the cultural journal Kringsjaa'. In 1910 she became editor of the paper Kringsjaa. She was multilingual and translated several books into Nynorsk, including Personal Recollections of Joan of Arc, by the Sieur Louis de Conte written by Mark Twain and Quo vadis? written by Henryk Sienkiewicz.