The municipality has boundaries with Paranaiguara on the north; Santa Vitória-MG on the south and east; and Caçu on the west.

The economy is based on tourism, subsistence agriculture, cattle raising, services, public administration (802 workers in 2003), and small transformation industries.

There are warehouses both private and public for storing grains (mainly soybeans), which are transported in ships thousands of kilometers to the sea.

One of the greatest tourist points of the region is the artificial beach on the banks of this reservoir, twice the size of Guanabara Bay, and formed by the building of the São Simão Dam.

São Simão is famous for its carnival celebration attracting major performers from around the country and thousands of tourists.

One of the most spectacular attractions is the Hydroelectric Plant of São Simão, located on the Paranaíba River.

In 1935 a bridge was built connecting the states of Goiás and Minas Gerais and the town began to prosper.

In 1975, with the building of the dam, a new city for 10,000 people was created with mercury lamps, paved streets, and modern schools.