Kauaʻi County, officially known as the County of Kauaʻi, is a county in the U.S. state of Hawaiʻi. It encompasses the islands of Kauaʻi, Niʻihau, Lehua, and Kaʻula. According to the 2020 Census, the population was 73,298. The county seat is Līhuʻe. The Kapa'a Micropolitan Statistical Area includes all of Kauai County.