Iinuma (written: 飯沼) is a Japanese surname. Notable people with the surname include:
- Masaaki Iinuma (飯沼 正明, 1912–1941), Japanese aviator
- Iinuma Sadakichi (飯沼 貞吉, 1854–1931), Japanese samurai
- Iinuma Yokusai (飯沼 慾斎, 1782–1865), Japanese botanist and physician
See also
edit- Iinuma Station, a railway station in Nakatsugawa, Gifu Prefecture, Japan