Sinān ibn ʿUlayyān or Sinān ibn al-Bannā (fl. 992 – c. 1028), also known by his laqab (honorific epithet) Ṣamṣām al-Dawla (Arabic: صمصام الدولة, lit. 'Lion of the Dynasty'), was a preeminent emir of the Banu Kalb tribe in Syria under early Fatimid rule. He was an ally of the Fatimids in several campaigns, until rebelling against them in alliance with the chiefs of the Arab tribes of Tayy and Kilab in 1025. Sinan attempted to take over Damascus from its Fatimid ruler, but died in 1028. His nephew Rafi ibn Abi'l-Layl reverted to allying with the Fatimids against the Tayy and Kilab.