Born in Chicago, Illinois, Erlenborn was a graduate of Loyola University Chicago and Loyola University Chicago School of Law. He represented his district for twenty years, from January 1965 to January 1985, a period which began with the 89th United States. Congress. He retired after serving in the 98th United States. Congress.
He died on October 30, 2005, at age 78, after suffering from Lewy body disease.
The majority of his papers and other materials created during his time in office are held at the archives of Benedictine University.