Puuwai (literally, "heart" in Hawaiian, ) is an unincorporated community in Kauaûi County, Hawaii, United States, and the only settlement on the island of Niihau. It is at the western coast of the small island, and Native Hawaiians who live in this village speak the Niûihau dialect of the Hawaiian language. Access to the town, as well as the whole island, is limited to Niihau residents; only official visitors and invited guests are permitted. Puuwai has a one-room schoolhouse.
Niihau is located about west of Kauai.
Puuwai is the westernmost community in the principal Hawaiian Islands.
The island features in the 1980 alternate history film The Final Countdown, as the "deserted spot" where characters Senator Samuel S. Chapman and Laurel Scott are to be left on the morning of the 1941 attack on Pearl Harbor. The film was set and filmed on board the real-life .