Many women serve as officers in the Marines and other branches of America's armed forces but the woman, who has not been identified publicly at her own request, is the first to finish the 13-week infantry officer training course.
"I am proud of this officer and those in her class," Marine Corps commandant General Robert Neller said in a statement.
"Marines expect and rightfully deserve competent and capable leaders, and these (Infantry Officer Course) graduates met every training requirement as they prepare for the next challenge of leading infantry Marines; ultimately, in combat," Neller added.
As an infantry officer, the woman, a lieutenant, will be assigned to lead a platoon of around 40 Marines. She will join the 1st Marine Division in Camp Pendleton, California, the Marines said.