Bierko was born in Rye Brook, New York, the son of Pat (Distillator) and Rex Bierko, who ran a local community theatre. Bierko's mother was a Jewish-born convert to Roman Catholicism. Bierko has said he is "very connected" to his Jewish heritage. His surname is Polish. He attended Blind Brook High School and then went on to Boston University intending to study broadcast journalism at the School of Public Communications but graduated from Northwestern University in 1986 with a BS in theater arts from the School of Speech.