The Marshall Islands marked its second consecutive Olympiad, at the 2012 Summer Olympics in London, from July 27 to August 12, 2012.

Middle-distance runner Haley Nemra was honored as the national flag bearer at the opening ceremony.

[4] The addition of the Marshall Islands along with Montenegro and Tuvalu the following year brought the total number of nations competing at the 2008 Summer Olympics to 205.

[13][14] Giordan Harris competed in the men's 50 meter freestyle, where he finished sixth in his heat and placed forty-sixth in the standings.

[15] Ann-Marie Hepler partook in the women's 50 meter freestyle, where she placed third in her heat and ranked forty-ninth in the standings.