The Suibu (Chinese: 須卜; pinyin: Xubu; Wade–Giles: Suibu, the part bu is a Chinese for "tribe") was a maternal dynastic tribe of the Xiongnu tribal confederation (Ch. Xiongnu) that flourished between 3rd century BCE to 4th century CE. Chinese annals noted that the Suibu tribe replaced the Huyan (呼衍、呼延) tribe, which was an earlier maternal dynastic tribe of the dynastic union with the paternal dynastic tribe Luanti (挛鞮). The traditional system of conjugal unions is a form of the nomadic exogamic society. The male members of the maternal dynastic line were not eligible for the Chanyu throne, only the male members of the Luanti line, whose father was a Luanti Chanyu, and mother was a Suibu Khatun (Queen) were eligible for the supreme throne. A Suibu could only become a Chanyu after a palace coup.
The tribe Huyan moved from the Right (Western) Wing, where the maternal dynastic tribe is traditionally assigned, to the Left (Eastern) Wing. The later Hou Hanshu chapter 89, l. 7b) stated that of the noble tribes other than Luanti, Huyan (呼衍、呼延), Suibu, Qiulin (丘林) and Lan (蘭 Lan Hsti-pu), Huyan already belonged to the dominating Left Wing, and Lan and Suibu belonged to the Right Wing. Hou Hanshu also names the dynastic Luanti tribe with a composite name Suiluanti (Ch. 虚连题 Xulianti), implying a merger of the two dynastic lines.
Suibu was a tribe that held some of the highest positions in the Eastern Xiongnu society, including the position of Khatun within the tribal confederacy, and the State Judge. A male head of the Suibu tribe held a third highest position in the state, Right Jükü-prince (Ch. 右屠耆王 Yu Tuqi-wang, 右贤王 Yu Xian-wang , Right Wise Prince). In that position, the Right Jükü-prince managed the daily affairs of the state, headed a considerable division of the army, was a first adviser to the Chanyu, and managed the foreign relations. Frequently, the Right Jükü-prince was sent as a personal envoy of the Chanyu to resolve difficult international problems, the Chinese annals often mention the Right Jükü-prince in that capacity.
The earliest annalistic record that mentioned a Right Jükü-prince by name refers to the events of the 121 BCE, when a Right Jükü-prince Hunie (渾邪王 Hunxie) killed an heir apparent Left Jükü-prince Huchjui (休屠王 Xiutu) and with 40,000 cavalry submitted to the Han Empire, establishing a 200,000 Suibu population in the Northern China.