| Name | God or Goddess | Description |
|---|---|---|
| Aegaeon | God | god of violent sea storms and ally of the Titans |
| Amphitrite | Goddess | sea goddess and consort of Poseidon |
| Benthesikyme | Sea nymph | daughter of Poseidon, who resided in Ethiopia |
| Brizo | Goddess | patron goddess of sailors, who sent prophetic dreams |
| Ceto | Goddess | Goddess of the dangers of the ocean and of sea monsters |
| Cymopoleia | Sea nymph | a daughter of Poseidon married to the Giant Briareus |
| Delphin | God | dolphin god or daimone |
| Eidothea | Sea nymph | prophetic sea nymph and daughter of Proteus |
| Glaucus | God | the fisherman's sea god and oracle |
| Leucothea | Goddess | a sea goddess who aided sailors in distress |
| Nereides | Sea nymph | |
| Arethusa | Sea nymph | a daughter of Nereus who was transformed into a fountain |
| Dynamene | Sea nymph | associated with the might and power of great ocean swells |
| Galene | Goddess | goddess of calm seas |
| Psamathe | Goddess | goddess of sand beaches |
| Thetis | God | leader of the Nereids who presided over the spawning of marine life in the sea |
| Nereus | God | the old man of the sea, and the god of the sea's rich bounty of fish |
| Nerites | a sea spirit who was transformed into a shell-fish by Aphrodite | |
| Oceanides | Sea nymph | sea nymphs, and patronesses of bodies of fresh waterSome notable Oceanides include: |
| Idyia | Sea nymph | wife of the Colchian king Aeetes, mother of Medea |
| Metis | Goddess | Zeus' first wife, whom Zeus impregnated with Athena and then swallowed. |
| Styx | Goddess | goddess of the river Styx |
| Oceanus | God | god of the Earth-encircling river Oceanus (the ocean), the fountain of all the Earth's fresh water |
| Potamoi | God | Gods of rivers and streams of the earthSome notable river gods include: |
| Achelous | God | the god of the Achelous River, the largest river in Greece, who gave his daughter in marriage to Alcmaeon. |
| Alpheus | who fell in love with the nymph Arethusa. | |
| Inachus | the first king of Argos and progenitor of Argive line through his son grandson Argus. | |
| Nilus | God | Egyptian river god and the father of numerous daughters that mingled with the descendants of Inachus. |
| Peneus | river god of Thessaly flowing from the foot of Pindus. He was the father of Daphne and Stilbe. | |
| Scamander | who fought on the side of the Trojans during the Trojan War. | |
| Palaemon | God | a young sea god who aided sailors in distress |
| Phorcys | God | god of the hidden dangers of the deep |
| Pontus | God | primordial god of the sea, father of the fish and other sea creatures, son of Gaia alone |
| Proteus | God | a shape-shifting, prophetic old sea god, and the herdsman of Poseidon's seals |
| Poseidon | God | king of the sea and lord of the sea gods; also god of rivers, flood and drought, earthquakes, and horses |
| Sangarius | God | a river god |
| The Telchines | sea spirits native to the island of Rhodes; the gods killed them when they turned to evil magic | |
| Actaeus | ||
| Argyron | ||
| Atabyrius | ||
| Chalcon | ||
| Chryson | ||
| Damon | ||
| Damnameneus | ||
| Dexithea | mother of Euxanthios by Minos | |
| Lycos | ||
| Lysagora | ||
| Makelo | ||
| Megalesius | ||
| Mylas | ||
| Nikon | ||
| Ormenos | ||
| Simon | ||
| Skelmis | ||
| Tethys | Goddess | goddess of the sources of fresh water, and the mother of the rivers, springs, streams, fountains, and clouds |
| Thalassa | Goddess | primeval goddess of the sea and consort of Pontos |
| Thaumas | God | god of the wonders of the sea |
| Thoosa | Goddess | goddess of swift currents |
| Triteia | daughter of Triton and companion of Ares | |
| Triton | fish-tailed son and herald of Poseidon | |
| Tritones | fish-tailed spirits in Poseidon's retinue |