| Mount Nyū | |
| Other Name: | 乳／ニュウ |
| Elevation M: | 2351.9 |
| Listing: | List of mountains and hills of Japan by height |
| Language: | Japanese |
| Pronunciation: | pronounced as /ja/ |
| Location: | Koumi, Nagano, Japan |
| Range: | Northern Yatsugatake Volcanic Group |
| Coordinates: | 36.0394°N 138.3706°W |
| Type: | Stratovolcano |
is a stratovolcano of the Northern Yatsugatake Volcanic Group in Koumi, Nagano Prefecture, Japan. This mountain is part of the Yatsugatake-Chūshin Kōgen Quasi-National Park.
There are several routes to reach to the top of Mount Nyū. One is from Shirokoma Pond, it takes one and half hours. Another major route is from Mount Naka.