Silene hawaiiensis is a rare species of flowering plant in the pink family known by the common names Hawai'i catchfly, Hawaiian catchfly and Sherff's catchfly. It is endemic to Hawaii, where it is known only from the island of Hawaii. It is threatened by the degradation of its habitat and it is a federally listed threatened species of the United States. This subshrub grows 15 to 40 centimeters tall and bears narrow leaves and greenish white flowers. The roots are spindle-shaped and sometimes grow exposed aboveground, which may help the plant survive.