Grand Ayatollah Sadr al-Din bin Saleh (Arabic: صدر الدين ابن صالح) (Heart of the religion) of Qom, Iran was a Twelver Shi'a religious scholar.
Sadr ed-Deen is also the patriarch of the Sadr family, a branch of Sharafeddine (Arabic:شرف الدين) family from Jabal Amel in Lebanon. The Sharafeddine family itself is a branch of the Nour eddine family, which traces its lineage to Musa al-Kazim (the seventh Shi'a Imam and through him to the first Imam, Ali ibn Abi Talib and Fatima Zahra, the daughter of Muhammad (d.632). The as-Sadr family has produced numerous Islamic scholars in Iran, Lebanon, and Iraq, including his son Ismail as-Sadr (d. 1919-1920) and his grandsons Musa as-Sadr (d.1978?) and Mohammad Baqir as-Sadr (d.1980).