Matsubase (松橋町 Matsubase-machi) was a town located in Shimomashiki District, Kumamoto, Japan.
On January 15, 2005 Matsubase was merged with the towns of Misumi and Shiranuhi, both from Uto District, and the towns of Ogawa and Toyono, all from Shimomashiki District, to form the new city of Uki and no longer exists as an independent municipality.
As of 2003, the town had an estimated population of 25,166 and the density of 659.66 persons per km². The total area was 38.15 km².