Mark Stiles Unit

Mark W. Stiles Unit is a Texas Department of Criminal Justice men's prison located in an unincorporated area of Jefferson County, Texas, near Beaumont. The unit, located along Farm to Market Road 3514, is 4 mi southeast of downtown Beaumont. The approximately 776 acre unit is co-located with the Gist Unit and the LeBlanc Unit.

The unit opened in June 1993. The unit serves as the University of Texas Medical Branch hub site for treatment of HIV and other infectious diseases. As a result, the Stiles facility houses many HIV positive prisoners. A hospice for prisoners with HIV opened at Stiles in 1997.

The unit has offered Buddhist meditation classes since 2003.

In 2011 the metal products plant closed; its operations were consolidated to the plants at the Coffield Unit and the Powledge Unit.

Notable prisoners

 * Elmer Wayne Henley
 * John Curtis Dewberry