Mirbag-e Jonubi Rural District () is in Mirbag District of Delfan County, Lorestan province, Iran. Its capital is the village of Dam Bagh Yusefabad.
At the National Census of 2006, its population (as a part of the Central District) was 6,636 in 1,426 households. There were 6,639 inhabitants in 1,597 households at the following census of 2011. At the most recent census of 2016, the population of the rural district was 5,819 in 1,665 households. The largest of its 43 villages was Mileh Khan, with 870 people.
In 2023, Itivand and Mirbag Districts were established, with two rural districts each that were transferred from Kakavand District and the Central District, respectively.