Jan Kjellström (born 1940, died 1967) was an orienteer from Sweden who played an important role in the development of the sport of orienteering in Great Britain. Kjellström, a son of Silva compass founder Alvar Kjellström, travelled to Great Britain to promote the sport. There, he helped to accelerate developments in orienteering competition, mapping and coaching. Kjellström died in a road accident early in the year of 1967.
1967 saw the first Jan Kjellström International Orienteering Festival or “JK”, held in memory of Jan Kjellström. The annual JK moved to Easter in 1969. The 1974 JK was the first British event to attract more than one thousand entrants.