Film:
* The Black Stallion (1979) - as Aletha
* The Last Unicorn (1982) - as Molly Grue
* The Secret of NIMH (1982) - as Mrs. Brisby (voice)
* The Muppet Movie (1979) - as Miss Piggy's "Mama" (uncredited)
* The Last Starfighter (1984) - as Officer's Wife
* The Jewel of the Nile (1985) - as Jill
* Batteries Not Included (1987) - as Mrs. Deets
* The Blob (1988) - as Nurse Sharon
* The 'burbs (1989) - as Mrs. Klopek
* Arachnophobia (1990) - as Mrs. Ashley
* The Secret of NIMH 2: Timmy to the Rescue (1998) - as Mrs. Brisby (voice)
* The Wild Thornberrys Movie (2002) - as The Old Woman (voice)
* The Princess Diaries 2: Royal Engagement (2004) - as Miss Lily
* A Lot Like Love (2005) - as Mom
* Superman Returns (2006) - as Mrs. Henderson
* The Spiderwick Chronicles (2008) - as Lucinda
* The Perfect Game (2009) - as Mrs. Perez
* The Muppets (2011) - as Miss Piggy's "Mama" (uncredited)
* The Secret Life of Pets (2016) - as Mel's Mom (voice)
* The Boss Baby (2017) - as Grandma (voice)
* The Secret Life of Pets 2 (2019) - as Mel's Mom (voice)
* The Boss Baby: Family Business (2021) - as Grandma (voice)
Television:
* The Waltons (1972-1981) - as Miss Emma
* The Mary Tyler Moore Show (1970-1977) - as various roles
* The Bob Newhart Show (1972-1978) - as various roles
* The Incredible Hulk (1978-1982) - as various roles
* The Love Boat (1977-1986) - as various roles
* Fantasy Island (1978-1984) - as various roles
* The Facts of Life (1979-1988) - as various roles
* Three's Company (1976-1984) - as various roles
* Taxi (1978-1983) - as various roles
* M*A*S*H (1972-1983) - as various roles
* Cagney & Lacey (1981-1988) - as various roles
* Murder, She Wrote (1984-1996) - as various roles
* The Golden Girls (1985-1992) - as various roles
* Frasier (1993-2004) - as various roles
* ER (1994-2009) - as various roles
* The West Wing (1999-2006) - as various roles
* Grey's Anatomy (2005-2023) - as various roles
* Modern Family (2009-2020) - as various roles
* The Good Place (2016-2020) - as various roles
* The Big Bang Theory (2007-2019) - as various roles
* The Kominsky Method (2018-2021) - as various roles
* Schitt's Creek (2015-2020) - as various roles
* Ted Lasso (2020-present) - as various roles
Note: This list may not be exhaustive, and there may be other film and television projects that Jo Ann Harris has been involved in.