Military Enlistment Opportunity Act of 2015

Amends citizenship and residency qualifications for enlistment in the U.S. Armed Forces to permit enlistment of additional persons who: (1) have resided continuously in a lawful status in the United States for at least two years, or (2) possess an employment authorization document issued by U.S. Citizenship and Immigration Services under requirements of the Department of Homeland Security (DHS) policy entitled Deferred Action for Childhood Arrivals.

Requires authorized enlistees who are not citizens or other nationals of the United States or lawfully admitted for permanent residence to be adjusted to the status of an alien lawfully admitted for permanent residence under an exception to specified provisions of Immigration and Nationality Act. (Such enlistees need not establish that they entered the United States prior to January 1, 1972, or comply with other specified requirements.)

Directs DHS to rescind such adjusted status if the person is separated from the armed forces under other than honorable conditions before the person served for a period or periods aggregating five years.

Deems any person who has received an award from the U.S. Armed Forces for engagement in active combat or active participation in combat to have satisfied specified naturalization requirements.