Marilyn McIntyre was born in Erie, Pennsylvania, the daughter of Jeanne Ellen (née Corzilius) and Roger McIntyre, an aeronautical engineer. She received her training and a Bachelor of Fine Arts degree at the North Carolina School of the Arts, and her Master of Fine Arts degree in the graduate program at Pennsylvania State University.
She had contract (series regular) roles in the television series Watch Over Me, Days of Our Lives as Jo Johnson, One Life to Live, Loving, and Search for Tomorrow, and recurring guest star roles on LA Law, Judging Amy, General Hospital: Night Shift, General Hospital, The Young and the Restless, and Ryan's Hope. Ms. McIntyre has had guest star roles on numerous television series including The Equalizer, Chicago Hope, The X-Files, Dark Skies, among others.