Silene spaldingii is a rare species of flowering plant in the pink family known by the common names Spalding's silene, Spalding's catchfly and Spalding's campion. It is native to eastern Washington, and eastern Oregon in the United States, as well as northern Idaho and northern Montana, where its distribution extends just into British Columbia, Canada. It is limited to the last remaining stretches of pristine prairie grassland in this region. It is threatened by the degradation and loss of its remaining habitat. It is federally listed as a threatened species in the United States and it is designated endangered by Canada's COSEWIC.