After his mother died, his father remarried Sandra Sorenson.

Dennis Parmenter attended North Polk High School, Iowa State University, and the Drake University School of Law.

He married Kathy Houge in October 1970, with whom he had three children.

Parmenter was an Assistant Story County Attorney, and in 1979, established his legal practice in Huxley.

[1] A Democrat, he was a member of the Iowa House of Representatives from 1999 to 2001 (62nd district).