al-Malik al-Afdal ibn Badr al-Jamali Shahanshah (1066-1121) was a vizier of the Fatimid caliphs of Egypt.

He was the son of Badr al-Jamali, an Armenian Mamluk. Badr was vizier for the Fatimids in Cairo from 1074 until his death in 1094, when al-Afdal succeeded him. Caliph Ma'ad al-Mustansir Billah died soon afterwards, and al-Afdal appointed al-Musta'li , a child, caliph, instead of al-Mustali's much older brother Nizar, who had been designated successor. Nizar revolted and was defeated in 1095; his supporters, led by Hassan-i-Sabah, fled west, where Hassan established the Hashshashin (Assassins).

At this time Fatimid power in Palestine had been reduced by the arrival of the Seljuk Turks. In 1097 he captured Tyre from the Seljuks, and Jerusalem in 1098 Jerusalem, expelling its Ortoqid governors in place of a Fatimid. The next year, Jerusalem was captured by crusaders; al-Afdal was at first unconcerned with them, assuming that they were Byzantine mercenaries and would be content with the capture of Antioch from the Seljuk Turks, also enemies of the Fatimids. When it became apparent that the crusaders would not rest until they had control of the city, al-Afdal marched out from Cairo, but was too late to rescue Jerusalem, which fell on July 15, 1099. On August 12, the crusaders under Godfrey of Bouillon surprised al-Afdal at the Battle of Ascalon and completely defeated him. Al-Afdal marched out every year to attack the newfound Kingdom of Jerusalem, and in 1105 attempted to ally with Damascus against them, but was defeated at Ramla. Al-Afdal and his army enjoyed success only so long as no European fleet interfered, but they gradually lost control of their coastal strongholds. The crusaders remained in Jerusalem until the arrival of Saladin decades later.

Al-Afdal also introduced tax (iqta) reform in Egypt, which remained in place until Saladin took over Egypt. Al-Afdal was nicknamed Jalal al-Islam ("glory of Islam") and Nasir al-Din ("Protector of the Faith"). He was killed by the Hashshashin in 1121 and succeeded by Al-Bata'ihi.