Sergipe (Portuguese pronunciation: [sɛʁˈʒipi]) (officially the State of Sergipe), is the smallest state of the Brazilian Federation, located on the northeastern Atlantic coast of the country. It borders on two other states, Bahia to the south and west and Alagoas to the north, and to the east is the Atlantic Ocean. Aracaju is the capital and the largest city of the state.

As with most of the states in northeastern Brazil, inland Sergipe is almost entirely savanna (caatinga), and its coastline is characterized by mangroves, swamps and sandy beaches. A small strip of tropical rainforest runs down the coast.

The São Francisco River forms its northern boundary, and the drainage of the northern part of the state is northward and eastward to that river. The southern half of the state slopes eastward and is drained directly into the Atlantic through a number of small rivers, the largest of which are the Irapiranga (whose source in the state of Bahia is called Vasa Barris at its mouth), the Real and the Cotinguiba. These streams are navigable for short distances, but are obstructed by sandbars at their mouths, and that of Cotinguiba is especially dangerous. The surface of the state resembles, in part, that of Bahia, with a zone of forested lands near the coast and beyond this forested zone lies a higher zone of rough open country, called agreste. There is a sandy belt along the coast, and the western frontier is slightly mountainous. The land in between is very fertile, especially in the forested region where the rainfall is abundant. Further inland, the year is divided into wet and dry seasons with occasional prolonged droughts. These are pastoral areas, and the lower fertile lands are cultivated. There are no good ports on the coast because of the sandbars at the mouths of the rivers.