The municipality of Sober has an area of 133.52 square kilometres. It is in the southern part of the Province of Lugo, in the Terra de Lemos Region. It comprises 22 parishes. Its geographical boundaries are Monforte de Lemos and Pantón to the north, the River Sil to the south, which marks the border with the Province of Ourense; Monforte to the east, and Pantón to the west.

Sober is mainly accessible by the national road N-120, which connects it to the Ourense-Vigo motorway to the east and to the Spanish Meseta Central (Inner Plateau) to the west. There are also regional roads that link Sober to Pantón, Monforte de Lemos and Castro Caldelas. By train, the line runs through the north, with a station at Canaval and a halt in Areas.

The municipality is served by an extensive network of paved country roads, narrow lanes and some unpaved roads, that connect and provide access to villages and hamlets.