Mishima is located in far eastern Shizuoka Prefecture, at the northern end of Izu Peninsula and in the foothills of Mount Fuji.

Under the Ritsuryō administration system established in the Nara period, Mishima was made capital of Izu Province.

With the establishment of the modern municipalities system of 1889, the area was reorganized as Mishima Town within Kimisawa District.

Mishima received its first train connection in 1898 when the predecessor of the Izuhakone Railway established what is now Shimo-Togari Station.

However, Mishima's fortunes revived strongly only after the Tanna Tunnel was completed in 1934, connecting the town to the Tōkaidō Main Line railway between Tokyo and Shizuoka.

It became a stop on the Tōkaidō Shinkansen from 1969, leading to an expansion in population, as the line made it possible to commute to Tokyo.

Mishima has a mayor-council form of government with a directly elected mayor and a unicameral city legislature of 22 members.