In Greek mythology, Chryseis (//, Ancient Greek: Χρυσηΐς, romanized: Khrysēís, pronounced [kʰrysɛːís]) is a Trojan woman, the daughter of Chryses. Chryseis, her apparent name in the Iliad, means simply "Chryses' daughter"; later writers give her real name as Astynome (Ἀστυνόμη). The poet Tzetzes describes her to be "very young and thin, with milky skin; had blond hair and small breasts; nineteen years old and still a virgin".
As the "golden one" she is also the title-giving character of the Baroque alchemical epic Chryseidos Libri IIII (1631).
Astynome was sent by her father for protection, or, according to others, to attend the celebration of a festival of Artemis in Hypoplacian Thebe or in Lyrnessus where she was taken as prisoner by Achilles. According to some, she was the wife of Eetion, king of Lyrnessus (usually described as the ruler of nearby Cilician Thebe), who was killed by the son of Peleus during his campaigns against the allies of Troy.
In the first book of the Iliad, during the distribution of the booty brought by Achilles, she was given to Agamemnon by unanimous decision in view of his kingly office. As a war prize, Agamemnon who admitted that she was finer than his own wife Clytemnestra, enslaved Chryseis and refused to allow her father to ransom her even though the priest of Apollo offered the Mycenaean king gifts of gold and silver. Apollo then sent a plague sweeping through the Greek armies and Agamemnon was forced to give Chryseis back in order to end it. He sent Odysseus to return the maiden to Chryses. Agamemnon compensated himself for this loss by taking Briseis from Achilles, an act that offended Achilles who refused to take further part in the Trojan War.
After the attack on Rhesus and his Thracian armies, Chryses came to the Greeks to thank them for returning his daughter, Astynome. Because of this kindness, and because he knew that his daughter had been properly treated, he brought her back for Agamemnon to have. A later Greek legend, preserved in Hyginus' Fabulae, states that she had a son named after her father by Agamemnon. In the city of Thebes in Asia Minor, Chryseis gave birth to Chryses and declared him to be a son of Apollo. This took place when she was released shortly as a prisoner and allowed to return to her hometown.
A few years later, when the children of Agamemnon, Orestes and Iphigenia took refuge in the Island of Sminthos, now the home of Chryseis and her family, she proposed surrendering the fugitives to King Thoas. Her son Chryses, learning they were his half-siblings, helped them to kill the Taurian king.
In medieval literature, Chryseis is developed into the character Cressida.