In Greek mythology, Pandora’s father-in-law was Iapetus, according to traditions naming Epimetheus’s parent.
Iapetus was one of the Titans and is identified in Hesiod’s Theogony as the father of Atlas, Menoetius, Prometheus, and Epimetheus. Since Pandora married Epimetheus, Iapetus becomes her father-in-law within that family genealogy.
This relationship is an indirect detail rather than a central event in the Pandora story. It connects Pandora’s myth to the broader Titan family, especially the four brothers whose stories explain different human or cosmic traits. Prometheus represents foresight and resistance to Zeus, while Epimetheus represents hindsight and accepts Pandora.
Genealogies can vary across Greek mythological sources, and “father-in-law” is a modern relational description rather than a title used by Hesiod. The answer follows the standard genealogy in which Iapetus is Epimetheus’s father and Pandora is Epimetheus’s wife.