Born as Diane Irgens, she made her screen debut in the 1946 film Ginger.
Jergens was featured in such 1950s films as The FBI Story with James Stewart and Desk Set starring Spencer Tracy and Katharine Hepburn. Her other films included leading roles in High School Confidential and Island of Lost Women.
She was married to actor Peter Brown between 1958-1960; he was a co-star of the ABC/Warner Brothers western series, Lawman. In 1962, she wed musician and Songwriter Randy Sparks.
She went on appearing in various television shows such as Dragnet, The Danny Thomas Show, The Addams Family, and 77 Sunset Strip. She retired from acting in 1966.