William Hartzell (February 20, 1837 – August 14, 1903) was a U.S. Representative from Illinois.

In 1853 Hartzell returned to the United States and moved to Randolph County, Illinois.

He was admitted to the bar in 1864 and commenced practice in Chester, Illinois.

He served as judge of the third judicial circuit of Illinois 1897–1903.

This article incorporates public domain material from the Biographical Directory of the United States Congress