Abū ʿAmr Muḥammad ibn ʿUmar ibn ʿAbd al-ʿAzīz al-Kashshī (Arabic: أبو عمرو محمد بن عمر بن عبد العزیز الکَشّي), died 941 or 951 or 978, known as al-Kashshi or (in Persian) as Kashshi, was a Twelver Shi'ite scholar specializing in biographical evaluation (ʿilm al-rijāl) and hadith studies.
[5][6][7][8] Al-Kashshi's original work is now lost, but parts of it survive in an abridgement made by Shaykh Tusi (995–1067) called the Ikhtiyār maʿrifat al-rijāl.
However, he is known to have been a contemporary of Muhammad ibn Ya'qub al-Kulayni (864–941), author of the Kitāb al-Kāfī.
However, one work known as the Rijāl al-Kashshī survives in an abridgement made by Shaykh Tusi (995–1067), called the Ikhtiyār maʿrifat al-rijāl.
[13][14] The Ikhtiyār maʿrifat al-rijāl ranks as one of the four most important works in the Shi'ite biographical (rijāl) literature.