The comedy will focus on a recently divorced mother (Reba McEntire) who must raise her children while working to reignite her singing career.
Tomlin will play Shirley, the mother of McEntire's Reba Gallagher, according to Deadline.
Her recent television credits include roles on Desperate Housewives, Damages and Lisa Kudrow's Web Therapy.
Malibu Country is being penned by Kevin Abbott, who previously worked with McEntire on her sitcom Reba. His past work includes Golden Girls, Roseanne and My Name Is Earl.
McEntire will also executive produce the pilot, with Mindy Schultheis, Michael Hanel, Narvel Blackstock, Dave Stewart and Pam Williams.
Other comedy pilots in the works at ABC include an untitled sitcom starring Mandy Moore and How to Live With Your Parents for the Rest of Your Life featuring Scrubs actress Sarah Chalke.
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