Ruth (רות, Hebrew for "compassion") was a Moabite woman whose father-in-law, Elimelech, had settled in the land of Moab. On the death of Elimelech and Mahlon, Naomi came with Ruth, her daughter-in-law, who refused to leave her, to Bethlehem, the old home from which Elimelech had migrated. There she had a rich relative, Boaz, to whom Ruth was eventually married. She became the mother of Obed, the grandfather of King David. According to the New Testament she is among the maternal progenitors of Jesus (Matt. 1:5).

In an attempt to identify Ruth in terms of other biblical figures, the Talmud claims that she was the daughter of the Moabite king Eglon, who figured briefly in the Book of Judges. This can also be seen as an attempt to provide a royal lineage to David. There is, however, no basis in the actual verses for such an assertion.

This story is told in the Book of Ruth, a part of the Tanakh (Hebrew Bible) and the Christian Old Testament.