|Native name||Mogami-gawa (Japanese)|
|Mouth||Sea of Japan|
|0 m (0 ft)|
|Length||229 km (142 mi)|
|Basin size||7,040 km2 (2,720 sq mi)|
|• average||392 m3/s (13,800 cu ft/s)|
The Mogami River (最上川, Mogami-gawa) is a river in Yamagata Prefecture, Japan.
It is 224 km long and has a watershed of 7,040 km2. It is regarded as one of the three most rapid rivers of Japan (along with the Fuji River and the Kuma River).
The river rises from southern Yamagata Prefecture and flows to the north, and turns west at Shinjō and flows into the Sea of Japan at Sakata. Water transportation once flourished on the river and carried local products such as safflowers and rice to the Kansai region.
The Mogami River appears as an utamakura in Japanese poetry, with the influential 17th-century poet Matsuo Bashō composing several hokku regarding the river during his travels alongside it. Some were revised as haiku in the memoir of his journeys, including this well-known poem:
The character Yūko Aioi in the Nichijou manga has inner monologues in haiku form, all ending with the name of the river as a complete non sequitur.
Mogami-gawa is also the name of the anthem of Yamagata Prefecture written by Emperor Hirohito. The Japanese Navy had two different cruisers named Mogami.