Senegal is situated on the western bulge of Africa and has borders with Mauritania to the north and northeast, Mali to the east, Guinea and Guinea Bissau to the south and the Atlantic Ocean to the west. It surrounds Gambia on three sides.

The northern part of the Senegal coast is made up of dunes and to the south are muddy estuaries. Behind the coast is a sandy plain, which extends north to the floodplain of the Senegal River. The Casamance Region in the south, isolated from the rest of Senegal by the Gambia, is low but more varied in relief, while to the southeast lie the Futa Jallon foothills, which rise to a maximum altitude of just above 1,600 ft. Much of the northwest of Senegal is semi-desert, but the center and most of the south, except for the forest of Casamance, are open savannah country. The major rivers - the Senegal, Saloum, Gambia and Casamance - flow from east to west.