Abu Sahl Hamdawi (also spelled Hamduni, Hamdavi and Hamdu'i), was a Persian statesman and military officer of the Ghaznavids, and served briefly as the vizier of Sultan Muhammad in 1030.
Hamdawi belonged to a distinguished and rich family of noble origins, and had his own palace, which, according to Farrukhi Sistani, was "finer than the palace of Kisra". This has recently made some scholars claim that Hamdawi's ancestry goes back to ancient Persian families.
Hamdawi, during his youth, served in the Ghaznavid army, and was also a student (or assistant) of Ahmad Maymandi. He later entered the court of Mahmud of Ghazni, where he shortly was appointed as the fiscal administrator of the Ghaznavid capital of Ghazni and India. In 1030, Mahmud died and was succeeded by his son Muhammad, who appointed Hamdawi as his vizier, but was, however, shortly overthrown by his more experienced brother Mas'ud I, who shortly appointed Ahmad Maymandi as his vizier, while appointing Hamdawi as the fiscal administrator of the entire Ghaznavid Empire.
In 1033, Hamdawi was appointed as the governor of Jibal, which was then held under the control of the Kakuyid ruler Muhammad ibn Rustam Dushmanziyar, who was a vassal of the Ghaznavids. However, Muhammad kept rebelling against Mas'ud I, and Hamdawi was shortly sent to deal with the latter, which he managed to accomplish. During the same period, Hamdawi had to protect Jibal from marauding Oghuz Turks who had arrived in the region from their steppes north to Khwarazm. Hamdawi managed to defeat the Turks, and then had their chief including another important member of their group captured.