Lorna Elizabeth Tuck Colbert died Wednesday, The Hollywood Reporter said.
Colbert, who showed a one-hour special with Paul McCartney on Wednesday, canceled Thursday's "Colbert Report," which was replaced with a repeat on the Comedy Channel.
Her obituary in The (Charleston) Post and Courier called Lorna Colbert, a devout Roman Catholic, "an accomplished artist, a church leader, a businesswoman, a supporter of the arts and a woman whose profound faith was apparent in her daily life." She was also described as "the matriarch of a family of 82."
Lorna Colbert was born in Larchmont, N.Y.
She was the mother of 11 children.
Her husband, Dr. James William Colbert Jr., moved the family to Charleston when he became dean of the Medical School of South Carolina. He was killed in a plane crash in 1974 with two of their sons, and another son also predeceased her.
One of Lorna Colbert's three daughters, Elizabeth Colbert Busch, ran unsuccessfully for Congress this year as a Democrat in a special election in South Carolina.
Last year, Stephen Colbert suspended his show while his mother was having health problems.
"Evidently, having 11 children makes you tough as nails -- confidential to a lovely lady," he said when he returned.
The funeral mass and burial were to be private.