Anan is located in the southeastern part of Tokushima Prefecture and is the easternmost municipality on the island of Shikoku.

The east faces the Kii Channel and the Pacific Ocean, and is the northern end of Muroto-Anan Kaigan Quasi-National Park.

Precipitation is high, but there is a pronounced difference between the wetter summers and drier winters.

Anan has a mayor-council form of government with a directly elected mayor and a unicameral city council of 28 members.

In terms of national politics, the city is part of Tokushima 1st district of the lower house of the Diet of Japan.

In modern times, it has been associated with Nichia, a global LED and electronic materials manufacturer which has its headquarters and several factories in the city.