Mataiva is a coral atoll in the Tuamotu Archipelago. It is located in the Palliser group, and is the westernmost of the Tuamotus. The nearest atoll, Tikehau , is located 35 km (21 mi.) to the east. Rangiroa is located 79 km (47 mi.) to the east, and Tahiti is 311 km (195 mi.) to the south.

The atoll's oval-shaped lagoon is 5.3 km (3.2 mi.) wide and 10 km (6 mi.) long, and is almost completely surrounded by land. The coral at the bottom of the lagoon is of poor quality, much of it having been destroyed in the latter part of 1980. In the lagoon are about 70 large basins, whose depths can reach up to 10 m (35 ft.), in which rich phosphate deposits have been discovered. To date, the inhabitants have successfully resisted its exploitation. The lagoon is open to the sea at a break in the northwest, site of Pahua , the only village, as well as a number of narrow passages along the south-central part of the reef. These shallow passages are known as the "nine eyes". There are also a number of small islets located within the lagoon itself.

Mataiva's primary export is vanilla, cultivated at a small plantation on the interior of the island. The islands are covered with coconut palms, the source of the other main economic activity: copra production.

In the southeastern part of the main island is an ancient ceremonial platform (marae in Tuamotuan ), called Marae Papiro, after its association with a pre-Christian turtle cult. It is constructed of large blocks of cut coral.

Pahua, the only village, lies on the west end of the atoll, on both sides of an unnavigable pass in the reef. The 110 m (360 ft.) concrete levee, which connects the two halves of the village, is the longest bridge in French Polynesia.

The first European to visit Mataiva was the Russian explorer Fabian Gottlieb von Bellinghausen , on July 30, 1820.