was a town located in Wake District, Okayama Prefecture, Japan.
As of 2003, the town had an estimated population of 5,254 and a density of 59.27 persons per km<sup>2</sup>. The total area was 88.65 km<sup>2</sup>.
On March 22, 2005, Yoshinaga, along with the town of Hinase (also from Wake District), was merged into the expanded city of Bizen.