Yui was a town located in Ihara District, Shizuoka Prefecture, Japan. As of October 1, 2008, the town had an estimated population of 9,085 and a density of 394.5 persons per km2. The total area was 23.03 km2. On November 1, 2008, Yui was merged into the Shimizu-ku ward of the expanded city of Shizuoka. Ihara District was dissolved as a result of this merger.