Abdanan County () is in Ilam province, Iran. Its capital is the city of Abdanan. The previous capital of the county was the village of Sarabbagh, (now a city).
The region was once part of the Sasanian Empire. During that time the Sasanians built Posht Qaleh Abdanan Castle in what is now Abdanan County. The castle still stands today although it is now in ruins. After the 2006 National Census, the village of Sarabbagh was elevated to the status of a city.
The county is populated by Kurds and Lurs.
At the time of the 2006 census, the county's population was 45,830 in 9,358 households. The following census in 2011 counted 46,977 people in 11,256 households. The 2016 census measured the population of the county as 47,851 in 13,188 households.
Abdanan County's population history and administrative structure over three consecutive censuses are shown in the following table.