was a village located in Senboku District, Akita Prefecture, Japan.
In 2003, the village had an estimated population of 4,529 and a density of 45.82 persons per km<sup>2</sup>. The total area was 98.85 km<sup>2</sup>.
On March 22, 2005, Nangai, along with the city of Ōmagari; and the towns of Kamioka, Kyōwa, Nakasen, Nishisenboku, Ōta and Semboku (all from Senboku District), merged to create the city of Daisen.
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Emblem of Nangai, Akita (1960–2005).svg|Chapter seal
Flag of Nangai, Akita (1960–2005).svg|Flag
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