Gunnar Hansen Horn (25 June 1894 – 15 July 1946) was a Norwegian petroleum geologist and Arctic explorer.

In addition to his purely scientific work, Horn also had administrative duties in the Arctic islands.

[3][6] During 1930, he headed the scientific expedition on the sealing vessel M/S Bratvaag which sailed under captain Peder Eliassen.

The expedition located the camp of Swedish Arctic scientist Salomon August Andrée on Kvitøya.

[7] In 1932 he went on ship Veslemari to East Greenland to establish the Storfjord, Finnsbu and Torgilsbu stations as part of the Norwegian contribution to the International Polar Year 1932–33.