Douglas J. Feith (born July 16, 1953) served as the Under Secretary of Defense for Policy for United States President George W. Bush from July 2001 until August 2005. His official responsibilities included the formulation of defense planning guidance and forces policy, United States Department of Defense (DoD) relations with foreign countries, and DoD's role in U.S. Government interagency policymaking.

Upon his resignation, Feith joined the faculty of the Edmund A. Walsh School of Foreign Service at Georgetown University, as a Professor and Distinguished Practitioner in National Security Policy for a two year stint.

Feith is the Director of the Center for National Security Strategies and a Senior Fellow at the Hudson Institute, a public policy think-tank.