Kjartan Jóhannsson (born 19 December 1939) an Icelandic diplomat, politician, former cabinet minister, and professor.
Kjartan was Ambassador of Iceland to, among others, the European Union in Brussels, Belgium, as well as the UN and other international organizations in Geneva.
He was secretary general of EFTA, a member of the Icelandic Parliament (Alþingi), chairman and vice chairman of the Icelandic Social Democratic Party, Minister of Fisheries and Commerce, a consultant in management and management science, and an associate professor at the University of Iceland.