Esther Before Ahasuerus is a painting by the 17th-century Italian artist Artemisia Gentileschi. It shows the biblical heroine Esther going before Ahasuerus to beg him to spare her people. The painting is now in the Metropolitan Museum of Art in New York, having been donated to the museum by Elinor Dorrance Ingersoll in 1969. It is one of Gentileschi's lesser known works, but her use of lighting, characterization, and style help in successfully portraying Esther as a biblical heroine as well as the main protagonist of the work.

Esther, originally Hadassah, is the eponymous heroine of the Book of Esther in the Hebrew Bible. According to the biblical narrative, which is set in the Achaemenid Empire, the Persian king Ahasuerus falls in love with Esther and marries her. His grand vizier Haman is offended by Esther's cousin and guardian Mordecai because of his refusal to bow before him; bowing in front of another person was a prominent gesture of respect in Persian society, but deemed unacceptable by Mordecai, who believes that a Jew should only express submissiveness to God. Consequently, Haman plots to have all of Persia's Jews killed, and eventually convinces Ahasuerus to permit him to do so. However, Esther foils the plan by revealing and decrying Haman's plans to Ahasuerus, who then has Haman executed and grants permission to the Jews to take up arms against their enemies; Esther is hailed for her courage and for working to save the Jewish nation from eradication.