Mutsu Province (陸奥国 Mutsu no kuni?) was an old province of Japan in the area of Fukushima, Miyagi, Iwate and Aomori Prefectures and the municipalities of Kazuno and Kosaka in Akita Prefecture.
Mutsu Province is also known as Ōshū (奥州?) or Michinoku (陸奥 or 道奥?). The term Ōu (奥羽?) is often used to refer to the combined area of Mutsu and the neighboring province Dewa which make up the Tōhoku region.
Mutsu, on northern Honshū, was one of the last provinces to be formed as land was taken from the indigenous Emishi and became the largest as it expanded northward. The ancient capital of the Kinai government was Tagajō in present-day Miyagi Prefecture.