Its length is about 603 km (375 mi) from the confluence of Djérem and Lom River.

Djerem is the longest source of Sanaga River with a total length of 464.5 km.

[3] It is formed by the confluence of the Djérem and Lom Rivers in the north of the East Region.

[4] The Sanaga River forms a boundary between two tropical moist forest ecoregions.

The Cross-Sanaga-Bioko coastal forests lie to the north between the Sanaga River and the Cross River of Nigeria, and the Atlantic Equatorial coastal forests extend south of the river through southwestern Cameroon and Equatorial Guinea, Gabon, the Republic of the Congo, Cabinda and the Democratic Republic of the Congo.