The Xubu was a tribe of the Xiongnu people that flourished between the 3rd century BCE and the 4th century CE. According to Chinese annals, the Xubu replaced the Huyan tribe, which had served as an earlier maternal dynastic tribe within a dynastic union alongside the paternal dynastic tribe known as Luandi.
The social structure of these tribes was characterized by a nomadic exogamic society involving a traditional system of conjugal unions. Within this framework, eligibility for leadership was strictly regulated; only male members of the Luandi line—specifically those whose fathers were Luanti Chanyus and mothers were Xubu Khatuns (Queens)—were eligible to become chanyu. A member of the Xubu tribe could only attain the position of chanyu following a palace coup.