See also: Mutsu Province.
| Native Name: | Japanese: 陸奥国 |
| Conventional Long Name: | Rikuō Province |
| Subdivision: | Province |
| Nation: | Japan |
| P1: | Mutsu Province |
| S1: | Prefectures of Japan#Former prefecturesTonami Prefecture |
| S2: | Prefectures of Japan#Former prefecturesShichinohe Prefecture |
| S3: | Prefectures of Japan#Former prefecturesHirosaki Prefecture |
| S4: | Prefectures of Japan#Former prefecturesKuroshi Prefecture |
| S5: | Prefectures of Japan#Former prefecturesHachinohe Prefecture |
| Today: | Iwate Prefecture Aomori Prefecture |
| Year Start: | 1869 |
| Year End: | 1871 |
| Image Map Caption: | Map of Japanese provinces (1869) with Rikuō Province highlighted |
, officially called was an old province of Japan in the area of Iwate and Aomori prefecture.[1]
It was also known as or . In the Meiji era, the province was cut down to cover only present-day Aomori and given the new name Rikuō Province, which retained the original kanji.[2]
On December 7, 1868 (January 19, 1869 in the Gregorian calendar), four additional provinces (Rikuchū, Rikuzen, Iwaki, and Iwashiro) were separated from Mutsu, leaving only a rump corresponding to today's Aomori Prefecture (with Ninohe District of Iwate Prefecture). At the same time, while the characters of the name were unchanged, the official reading was changed to the on'yomi version "Rikuō".[2]
Mutsu (Rikuō) Province consisted of nine districts: