Grand Ayatollah Sayyid Abu al-Hasan al-Musawi al-Isfahani (Arabic: أبوالحسن الموسوي الأصفهاني; 1861–November 4, 1946) was an Iranian-Iraqi Shia marja'. al-Isfahani became the leading marja' of the Shia world after the death of Muhammad-Hussein al-Naini.