Izumi (和泉国; -no kuni) or Senshu (泉州 senshū) was a province of Japan, which today composes the south-western part of Osaka Prefecture (not including the city of Osaka itself).

The ancient capital was probably in the modern suburb of Izumi. Izumi included the large seaport of Sakai, and was usually held by whoever ruled Osaka Castle and Settsu Province.