The BBC, citing a statement from Creative Artists Agency, reported she died on Friday at her home in Los Angeles following a brief illness.
O'Hara also portrayed Kate McCallister, the mother of Macaulay Culkin's character in the movie Home Alone and Delia Deetz in the film Beetlejuice.
O'Hara's portrayal of Rose in Schitt's Creek earned her the 2020 Emmy for best comedy actress and helped propel the TV show to awards season dominance at the 2021 Golden Globes.
The movie star was born in Toronto, Canada, and was one of seven children. Her first experience of acting was when she played the Virgin Mary in a Nativity play.
O'Hara worked as a waitress at the Second City Theater in Toronto after leaving high school. As a waitress, she came across the likes of Dan Aykroyd, and Joe Flaherty.
"I was lucky enough to watch everybody," she told People in 2024.
O'Hara eventually joined the company in 1974. However, she later confessed to feeling anxious whenever she was on the stage.
"My crutch was, in improvs, when in doubt, play insane. Because you didn't have to excuse anything that came out of your mouth. It didn't have to make sense," she admitted to The New Yorker in 2019.
O'Hara eventually landed a role on a TV sketch show called Second City Television, which aired on NBC in the 80s. The actress became famous for her impressions of various well-known celebrities, including Meryl Streep and Brooke Shields.
O'Hara made her film debut in 1980, when she starred alongside the likes of John Candy and Eugene Levy in Double Negative.
In 1988, she starred as Delia Deetz, the stepmother of Winona Ryder's Lydia, in the hit movie Beetlejuice, which proved to be a huge commercial success.
And in 1990, she played Macaulay Culkin's on-screen mother in Home Alone.
O'Hara - who reprised her role for 1992's Home Alone 2: Lost in New York - told People: "It's a perfect movie, isn't it?"
Culkin paid tribute to his on-screen mother on X.
"Mama, I thought we had time. I wanted more ... I had so much more to say. I love you I'll see you later."
O'Hara's other roles included Best in Show in 2000 and 2003's A Mighty Wind, as well as the Beetlejuice sequel in 2024.
In 2020, O'Hara won the Emmy for Outstanding Lead Actress in a Comedy Series for her performance in the hit TV sitcom Schitt's Creek, which was created by Eugene and Daniel Levy.
During her acceptance speech, O'Hara - who also won a Golden Globe and a SAG Award - said: "I will forever be grateful to Eugene and Daniel Levy for the opportunity to play a woman of a certain age, my age, who gets to fully be herself."
O'Hara is survived by her husband Bo and their sons Matthew and Luke.
with People
23°C