Jens Risom was born in Copenhagen, Denmark, on 8 May 1916. His father was a prominent architect, Sven Risom, a member of the school of Nordic Classicism. Jens Risom was trained as a designer at the Copenhagen School of Industrial Arts and Design (where he studied under Ole Wanscher and Kaare Klint. He was classmates with Hans Wegner and Børge Mogensen. In 1939, Risom travelled to New York City to study American design. He found it difficult to find work as a furniture designer in New York, however, and was forced to accept a number of textile designs that ultimately secured him freelance work with designer Dan Cooper.
In 1941, Risom teamed with entrepreneur Hans Knoll and in 1942, they launched the Hans Knoll Furniture Company with 15 of the 20 pieces in the inaugural "600" line designed by Risom. These works included stools, armchairs and lounges, made from cedar and surplus webbing-works which have since become design classics.
He launched his own firm, Jens Risom Design (JRD) on 1 May 1946.
Risom's reputation as a furniture designer continued to grow, and Risom began to promote Scandinavian design in home furniture to the broader American public. In 1961, Risom was one of six furniture designers featured in a profile in Playboy magazine. One of Risom's executive office chairs became famous when Lyndon B. Johnson chose to use it in the Oval Office.