Daisen is located in the flatlands of central Akita Prefecture. The area of the city is greater than the total metropolitan area of Tokyo. Daisen is bounded by the
Ōu Mountains in the east, the
Dewa Mountains in the center of the prefecture in the west, the former town of Kakumagawa between the
Omono River and the
Yokote River in the south, and the area slightly south of the summit of Mount Oishi in the north. The mountains of the Dewa Mountain Range in the western part of the city and the Ōu Mountains in the eastern part of the city surround the Senboku Plain in the northern part of the Yokote Basin.The Omono River, a first-class river, flows from the south to the northwest of the city. The highest peak in Daisen is Mount Kosugi (1,229 meters) in eastern Daisen.
Neighboring municipalities Akita Prefecture •
Akita •
Misato •
Semboku •
Yokote •
Yurihonjō Iwate Prefecture •
Nishiwaga Climate Daisen has a
humid continental climate (
Köppen climate classification Dfa / Cfa) with large seasonal temperature differences, with warm to hot (and often humid) summers and cold (sometimes severely cold) winters. Precipitation is significant throughout the year but is heaviest from August to October. The average annual temperature in Daisen is . The average annual rainfall is with August as the wettest month. The temperature is highest on average in August, at around , and lowest in January, at around . {{Weather box ==Demographics==