The Shilluk (Shilluk: Chollo) are a major Nilotic people of Southern Sudan, living on both banks of the river Nile, in the vicinity of the city of Malakal. Their language as Dhɔg Cɔllɔ or Dhɔ Cɔl, dhɔg being the Shilluk word for language and mouth. Before the second Sudanese civil war the Shilluk also lived in a number of settlements on the northern bank of the Sobat River, close to where the Sobat joins the Nile, with Doleib Hill as an important mission station.

The Shilluk are the third largest minority ethnic group of Southern Sudan, after the Dinka and their neighbors the Nuer.

Their language, the Shilluk language (or dhok-Chollo), belongs to the Luo branch of the Western Nilotic subfamily of Nilo-Saharan.

Historically the Shilluk were led by a king Reth who is considered to be from the divine lineage of the culture hero Nyikang, and whose health is believed to affect that of the nation. Formerly, their society was fairly hierarchical, with castes of royals, nobles, commoners, and slaves. Like most Nilotic groups, cattle-raising formed a large part of their economy; however, agriculture and fishing were more significant than usual, and most were sedentary.