In Greek mythology, Melantho (/mɪˈlænθoʊ/; Ancient Greek: Μελανθώ) may refer to the following women:

• Melantho, also called Melanthea, a Phthian princess as the daughter of King Deucalion and Pyrrha, daughter of Epimetheus and Pandora. She was not probably the sister of Hellen, Protogenea,^[1] Amphictyon,^[2] Pandora, Thyia,^[3] Orestheus, Marathonios, Pronous,^[4][5] and Candybus.^[6] Melantho was seduced by Poseidon the shape of a dolphin^[7] and by him, bore a son Delphus.^[8] In one account, Melantheia instead married King Hyamus of Hyampolis, son of Lycorus, and by him the mother of two daughters, Celaeno^[9] and Melanis,^[10] of whom either might have been mother of Delphus by Apollo.
• Melantho, also called Melantomice,^[11] an Argive queen as the wife of King Criasus. She was the mother of Phorbas, Ereuthalion and Cleoboea.^[12]
• Melantho, the disloyal maid of Penelope.^[13]