Abu al-Qasim Kashani (died after 1324) was a Persian historian from the Abu Tahir family, who was active during the late Ilkhanate era. He is notable for claiming that the vizier of the Ilkhanate, Rashid al-Din Hamadani, had stolen credit for the historical work Jami' al-tawarikh. Although modern scholarship regard Rashid al-Din as the overall author of the work, he is generally considered to have been aided by several assistants, including Kashani.
Kashani's major work is Tarikh-e Oljaytu (History of Öljaitü), covering Öljaitü's reign until his death in 1316. It is there that Kashani makes his allegations against Rashid al-Din. Since Rashid al-Din's account of this ruler in Jami' al-tawarikh is missing, whereas Kashani's work is complete, this gives some credibility to Kashani's claims.