Miss Jootsen was born on 20 December 1939 in Chicago, Illinois. She worked as a psychiatric nurse at a hospital there. She had two sons and raised a family. She divorced her husband in 1980 and did not decide to take up acting until she was 42 years old.
Kathryn Jootsen made her film debut in Grandview, U.S.A. (1984). In the Eighties she appeared in the shows Sable and Lady Blue. She appeared in the film The Package (1989). In the Nineties she appeared on such shows as Picket Fences, Chicago Hope, Grace Under Fire, 3rd Rock From the Sun, E.R., Roseanne, Murphy Brown, Frasier, Seinfeld, N.Y.P.D. Blue, The Nanny, and Home Improvement. She appeared in the films Eating Las Vegas (1997), Phoenix (1998), and Kiss Toledo Goodbye (1999). In the Naughts she was a regular on The West Wing, Joan of Arcadia, and Desperate Housewives. She appeared on such shows as Dharma & Greg, Spin City, The X-Files, The Drew Carey Show, Charmed, The King of Queens, Will & Grace, Everwood, My Name is Earl, Monk, and Scrubs. She appeared in such films as Wasabi Tuna (2003), Red Roses and Petrol (2003), Breaking Dawn (2004), Hostage (2005), Taking Your Life (2005), Wedding Crashers (2005), and Cheaper by the Dozen (2005).