Southern Lebanon is the geographical area of Lebanon comprising the South Governorate and the Nabatiye Governorate. These two entities were divided from the same province in the early 1990s. The Rashaya and Western Beqaa Districts, the southernmost districts of the Beqaa Governorate, in Southern Lebanon are sometimes included in this description.

The main cities of the region are Tyre, Sidon, Jezzine and inland Nabatiyeh. The cazas of Bint Jbeil, Tyre, and Nabatieh in Southern Lebanon are known for their large Shi'a Muslim population with a minority of Christians. Sidon is predominately Sunni, with the rest of the caza of Sidon having a Shi'a Muslim majority, with a considerable Christian minority, mainly Greek Catholics. The cazas of Jezzine and Marjeyoun have a Christian majority. The caza of Hasbaya has a Druze majority.

Southern Lebanon has featured prominently in the Israel-Lebanon conflict.