Merrin Dungey has one sister, Channing Dungey, who is also deeply involved in the film industry. She was the youngest recipient of the UCLA Acting Award. She earned a degree of Bachelor of Arts from UCLA. Dungey graduated in 1989 from Rio American High School in Sacramento, California. Dungey was also an accomplished ice skater. As a child, she was active in ballet and dance as well as piano.
Dungey was born in Sacremento, California, the daughter of Don Dungey, a general services manager.