The Global War on Terrorism Expeditionary Medal is a military decoration of the United States military which was created by Presidential Order of George W. Bush in March 2003. The decoration recognizes those military service members who have performed deployed overseas service in the War on Terrorism from September 11, 2001 to a date to be determined.

To be awarded the Global War on Terrorism Expeditionary Medal, a military service member must perform duty in a deployed status and must participate in designated anti-terrorism operation for a period of either 30 consecutive or 60 non-consecutive days of duty. For those who were engaged in combat, killed, or wounded in the line of the duty the time requirement is waived.

The term "deployed status" indicates either temporary or permanent orders to a duty station outside the borders of the United States of America with such duty being in direct support of anti-terrorism operations. For a service member to receive the Global War on Terrorism Expeditionary Medal, the deployment must also have taken place in a nation which is currently recognized as a base for anti-terrorism operations by the United States Department of Defense.

Currently, the Global War on Terrorism Expeditionary Medal may be awarded for approved operations performed in any of the following geographical areas: Afghanistan, Bahrain, Bulgaria, Crete, Cyprus, Diego Garcia, Djibouti, Egypt, Eritrea, Ethiopia, Iran, Iraq, Israel, Jordan, Kazakhstan, Kenya, Kuwait, Kyrgyzstan, Lebanon, Oman, Pakistan, Philippines, Qatar, Romania, Saudi Arabia, Somalia, Syria, Tajikistan, Turkey, Turkmenistan, United Arab Emirates, Uzbekistan, and Yemen.

The initial operations for which the Global War on Terrorism Expeditionary Medal is authorized include Operation Enduring Freedom and Operation Iraqi Freedom. Future operations, for which the GWOT Expeditionary Medal may be authorized, are at the discretion of United States component commanders upon approval from the Department of Defense.

The Global War on Terrorism Expeditionary Medal is a one time only decoration, however service stars may be authorized by component commanders for those who participated in extremely dangerous combat operations while performing service which entitled the GWOT Expeditionary Medal.

A similar decoration, known as the Global War on Terrorism Service Medal, also was created under the same Presidential Order that authorized the GWOT Expeditionary Medal. The primary difference between the two awards is that the service medal is intended for those who performed support duty within the United States while the expeditionary medal recognizes those who were deployed to foreign countries. For those participating in multiple operations, both the GWOT Service and GWOT Expeditionary Medal may be authorized, however both medals cannot be bestowed for service in a single operation.