Gunnar Johannes Viken (born 9 July 1948 in Levanger) is a Norwegian dairy farmer and politician for the Conservative Party. Since 2007 he has been county mayor of Nord-Trøndelag County Municipality. Viken has been a member of the Nord-Trøndelag County Council since 1999 and a deputy member of the Storting since 2013. Prior to his election as county mayor in 2007, he chaired the Conservative Party group in the county council for 4 years and the county agricultural board for 12 years. He entered politics as a member of the municipal council of Mosvik in the early 1980s. Viken did not seek his party's renomination to the county council in 2015.