This is a list of mammals of the Marshall Islands. There is one land mammal, the Polynesian rat. There are 27 marine mammals, one of which has been classified as vulnerable, the humpback whale.^[1]

The only extant land mammal species aside from humans on the islands is the Polynesian rat (Rattus exulans).

The 27 marine animals consist mostly of whales, dolphins, and porpoises.

Whales include the humpback whale, ginkgo-toothed beaked whale, Blainville's beaked whale,^[1] blue whale, sei whale, fin whale, and sperm whale.^[2]

Dolphins include the spinner dolphin, Fraser's dolphin, long-beaked common dolphin, and pygmy killer whale.^[1]

• "The IUCN Red List of Threatened Species: Mammals of the Marshall Islands". IUCN. 2001. Retrieved 22 May 2007.^{[dead link‍]}
• "Mammal Species of the World". Smithsonian National Museum of Natural History. 2005. Archived from the original on 27 April 2007. Retrieved 22 May 2007.
• "Animal Diversity Web". University of Michigan Museum of Zoology. 1995–2006. Retrieved 22 May 2007.