Joosten's publicist said the actress died in Los Angeles with her family by her side. In a statement, Joosten's family said the actress was "surrounded by love and humor" at the time of her death.
"We are laughing through our tears. We love you, Kathy, thanks for everything," the family said.
Joosten was an two-time Emmy-winning character actor. She portrayed Mrs. McCluskey on ABC's "Desperate Houswives," a character who kept a close eye on her Wisteria Lane neighbors. Joosten's character was killed off in the show's series finale last month.
Joosten also appeared on "The West Wing" as Mrs. Landingham, the president's secretary.
Aside from acting, Joosten served as a long-time Governor of The Academy of Television Arts and Sciences and a lung cancer advocate.
The Associated Press contributed to this report.