Omnibus Nonproliferation and Anti-Nuclear Terrorism Act of 2005

Omnibus Nonproliferation and Anti-Nuclear Terrorism Act of 2005 - Establishes in the Executive Office of the President an Office of Nonproliferation Programs whose primary function shall be to coordinate and lead: (1) U.S. efforts to curb terrorist access to nuclear technology, materials, or expertise; and (2) U.S. nonproliferation activities, including nuclear nonproliferation activities and activities to counter other weapons of mass destruction.

Amends specified Acts to remove or modify restrictions with respect to: (1) cooperative threat reduction programs, including destruction of chemical weapons and former Soviet weapons; (2) Department of Energy nonproliferation programs; and (3) cooperative threat reduction program and international nuclear materials protection and cooperation program fund use outside the former Soviet Union.

Expresses the sense of Congress with respect to: (1) liability protections for U.S. nonproliferation efforts in Russia; (2) expansion of the proliferation security initiative; and (3) international security standards for nuclear weapons and materials.

Authorizes appropriations to the Administrator for Nuclear Security for a comprehensive inventory of Russia's stockpile of strategic and non-strategic nuclear weapons.

Authorizes Federal fund use for non-defense research and development in Russia and the states of the former Soviet Union on environmental, proliferation detection, health and medicine, or energy technologies utilizing scientists in Russia and the states of the former Soviet Union who have expertise in nuclear, chemical, or biological weapons.

Sets forth congressional findings concerning the need to strengthen the Nuclear Nonproliferation Treaty.