Jan Alvar Kjellström (12 April 1940 – 12 January 1967) was a Swedish orienteer who played an important role in the development of the sport of orienteering in Great Britain.Kjellström was the son of Silva compass co-founder Alvar Estrid Petrus Kjellström and Elon Halvar Anna Engania.
He was the nephew of Björn Kjellström.
He travelled to Great Britain to promote the sport of orienteering.
There, he helped to accelerate developments in orienteering competition, mapping and coaching.
Kjellström went back to Sweden, where he was killed in a car accident in January 1967.