The Damascus affair is an 1840 incident in which the accusation of ritual murder is brought against members of the Jewish community of Damascus.

Eight notable Jews of Damascus are falsely accused of murdering a Christian monk, imprisoned and tortured.

Several of the imprisoned die of torture, and another is forced to convert to Islam.

In addition, the Muslim populace of Damascus falls upon the Jewish synagogue in the suburb of Jobar, pillages it, and destroys the scrolls of the Law.The affair draws wide international attention in particular due to the efforts of the Austrian Consul in Aleppo Eliahu Picciotto, who makes representations to Ibrahim Pasha, who then orders an investigation.

Sir Moses Haim Montefiore, backed by other influential westerners, leads a delegation to the ruler of Syria and Egypt, Mehemet Ali.

The negotiations in Alexandria continue from August 4 to August 28 and secure the unconditional release and recognition of innocence of the nine prisoners still remaining alive (out of thirteen).

Later in Constantinople, Montefiore persuades Sultan Abdülmecid I to issue a firman (edict) intended to halt the spread of blood libel accusations in the Ottoman Empire.

The prevailing contemporary interpretation of this event is that of being a part of a long history of false blood libel charges against Jews.