The Bank of Xenia is a historic former bank building in downtown Xenia, Ohio, United States. Built in 1835, it was the location of Greene County's first bank, which opened on June 1 of that year. For thirty years, the building was used as a bank, becoming the local branch of the State Bank of Ohio in 1846 and changing its name to First National Bank in 1863. After First National moved to a newer building in 1865, it was no longer used as a bank; among its later owners was A.C. Messenger, a physician who used it as his home and office. In the 1880s, the bank was a party to a lawsuit known as Xenia Bank v. Stewart, which was decided by the United States Supreme Court in 1885.