Puuwai (literally, "heart" in Hawaiian) is an unincorporated community in Kauai County, Hawaii, United States, and the only settlement on the island of . It is at the western coast of the small island, and Native Hawaiians who live in this village speak the Hawaiian language. The community lives as they did hundreds of years ago, and the modern amenities of life are extremely limited. 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 .
Puuwai is the westernmost community in Hawaii.