Tsukubamirai is located in southern Ibaraki Prefecture, in the low-lying marshy flatlands south of Lake Kasumigaura.

Ibaraki Prefecture Tsukubamirai has a Humid continental climate (Köppen Cfa) characterized by warm summers and cool winters with light snowfall.

The city of Tsukubamirai was established on March 27, 2006, from the merger of the town of Ina, and the village of Yawara (both from Tsukuba District).

Tsukubamirai has a mayor-council form of government with a directly elected mayor and a unicameral city council of 18 members.

In terms of national politics, the city is part of Ibaraki 6th district of the lower house of the Diet of Japan.